Đã cho một số n in tổng của tất cả các số chẵn từ 1 đến n trong C++

Sum of first 20 Even numbers is: 420
9
                 Sum of first n even numbers = n * (n + 1).
5
                 Sum of first n even numbers = n * (n + 1).
6
Sum of first 20 Even numbers is: 420
4
                 Sum of first n even numbers = n * (n + 1).
8

                 Sum of first n even numbers = n * (n + 1).
9
Sum of first n terms of an A.P.(Arithmetic Progression)
= (n/2) * [2*a + (n-1)*d].....(i)
where, a is the first term of the series and d is
the difference between the adjacent terms of the series.

Here, a = 2, d = 2, applying these values to eq.(i), we get
Sum = (n/2) * [2*2 + (n-1)*2]
    = (n/2) * [4 + 2*n - 2]
    = (n/2) * (2*n + 2)
    = n * (n + 1)
0

 

                 Sum of first n even numbers = n * (n + 1).
9
Sum of first n terms of an A.P.(Arithmetic Progression)
= (n/2) * [2*a + (n-1)*d].....(i)
where, a is the first term of the series and d is
the difference between the adjacent terms of the series.

Here, a = 2, d = 2, applying these values to eq.(i), we get
Sum = (n/2) * [2*2 + (n-1)*2]
    = (n/2) * [4 + 2*n - 2]
    = (n/2) * (2*n + 2)
    = n * (n + 1)
2

                 Sum of first n even numbers = n * (n + 1).
9
Sum of first n terms of an A.P.(Arithmetic Progression)
= (n/2) * [2*a + (n-1)*d].....(i)
where, a is the first term of the series and d is
the difference between the adjacent terms of the series.

Here, a = 2, d = 2, applying these values to eq.(i), we get
Sum = (n/2) * [2*2 + (n-1)*2]
    = (n/2) * [4 + 2*n - 2]
    = (n/2) * (2*n + 2)
    = n * (n + 1)
4

Sum of first 20 Even numbers is: 420
9
Sum of first n terms of an A.P.(Arithmetic Progression)
= (n/2) * [2*a + (n-1)*d].....(i)
where, a is the first term of the series and d is
the difference between the adjacent terms of the series.

Here, a = 2, d = 2, applying these values to eq.(i), we get
Sum = (n/2) * [2*2 + (n-1)*2]
    = (n/2) * [4 + 2*n - 2]
    = (n/2) * (2*n + 2)
    = n * (n + 1)
6

 

Sum of first 20 Even numbers is: 420
9
Sum of first n terms of an A.P.(Arithmetic Progression)
= (n/2) * [2*a + (n-1)*d].....(i)
where, a is the first term of the series and d is
the difference between the adjacent terms of the series.

Here, a = 2, d = 2, applying these values to eq.(i), we get
Sum = (n/2) * [2*2 + (n-1)*2]
    = (n/2) * [4 + 2*n - 2]
    = (n/2) * (2*n + 2)
    = n * (n + 1)
8

Sum of first 20 Even numbers is: 420
9
Sum of first 20 Even numbers is: 420
0
Sum of first 20 Even numbers is: 420
1

Sum of first n terms of an A.P.(Arithmetic Progression)
= (n/2) * [2*a + (n-1)*d].....(i)
where, a is the first term of the series and d is
the difference between the adjacent terms of the series.

Here, a = 2, d = 2, applying these values to eq.(i), we get
Sum = (n/2) * [2*2 + (n-1)*2]
    = (n/2) * [4 + 2*n - 2]
    = (n/2) * (2*n + 2)
    = n * (n + 1)
6

 

Sum of first 20 Even numbers is: 420
3

Sum of first 20 Even numbers is: 420
4
Sum of first 20 Even numbers is: 420
5

Sum of first 20 Even numbers is: 420
8

Sum of first 20 Even numbers is: 420
9
Sum of first 20 Even numbers is: 420
4
Sum of first 20 Even numbers is: 420
9

Sum of first 20 Even numbers is: 420
9
Sum of first 20 Even numbers is: 420
1____02
Sum of first 20 Even numbers is: 420
3

Sum of first 20 Even numbers is: 420
4
Sum of first 20 Even numbers is: 420
5
Sum of first 20 Even numbers is: 420
6
Sum of first 20 Even numbers is: 420
7

Sum of first 20 Even numbers is: 420
9
Sum of first 20 Even numbers is: 420
0
                 Sum of first n even numbers = n * (n + 1).
610

Sum of first n terms of an A.P.(Arithmetic Progression)
= (n/2) * [2*a + (n-1)*d].....(i)
where, a is the first term of the series and d is
the difference between the adjacent terms of the series.

Here, a = 2, d = 2, applying these values to eq.(i), we get
Sum = (n/2) * [2*2 + (n-1)*2]
    = (n/2) * [4 + 2*n - 2]
    = (n/2) * (2*n + 2)
    = n * (n + 1)
6

Java




                 Sum of first n even numbers = n * (n + 1).
612

                 Sum of first n even numbers = n * (n + 1).
613

                 Sum of first n even numbers = n * (n + 1).
614
                 Sum of first n even numbers = n * (n + 1).
615

                 Sum of first n even numbers = n * (n + 1).
614
                 Sum of first n even numbers = n * (n + 1).
617

 

                 Sum of first n even numbers = n * (n + 1).
618
                 Sum of first n even numbers = n * (n + 1).
619
                 Sum of first n even numbers = n * (n + 1).
700

Sum of first 20 Even numbers is: 420
9

Sum of first 20 Even numbers is: 420
9
Sum of first 20 Even numbers is: 420
2

Sum of first 20 Even numbers is: 420
9
                 Sum of first n even numbers = n * (n + 1).
70

Sum of first 20 Even numbers is: 420
9
                 Sum of first n even numbers = n * (n + 1).
707
Sum of first 20 Even numbers is: 420
4
Sum of first 20 Even numbers is: 420
5
Sum of first 20 Even numbers is: 420
4
Sum of first 20 Even numbers is: 420
7

Sum of first 20 Even numbers is: 420
9
Sum of first 20 Even numbers is: 420
8

                 Sum of first n even numbers = n * (n + 1).
9
Sum of first 20 Even numbers is: 420
4
                 Sum of first n even numbers = n * (n + 1).
736
                 Sum of first n even numbers = n * (n + 1).
737
                 Sum of first n even numbers = n * (n + 1).
738
                 Sum of first n even numbers = n * (n + 1).
739
                 Sum of first n even numbers = n * (n + 1).
770

 

                 Sum of first n even numbers = n * (n + 1).
9
                 Sum of first n even numbers = n * (n + 1).
3

                 Sum of first n even numbers = n * (n + 1).
9
                 Sum of first n even numbers = n * (n + 1).
5
                 Sum of first n even numbers = n * (n + 1).
6
Sum of first 20 Even numbers is: 420
4
                 Sum of first n even numbers = n * (n + 1).
777
                 Sum of first n even numbers = n * (n + 1).
778
                 Sum of first n even numbers = n * (n + 1).
779

Sum of first 20 Even numbers is: 420
00
Sum of first n terms of an A.P.(Arithmetic Progression)
= (n/2) * [2*a + (n-1)*d].....(i)
where, a is the first term of the series and d is
the difference between the adjacent terms of the series.

Here, a = 2, d = 2, applying these values to eq.(i), we get
Sum = (n/2) * [2*2 + (n-1)*2]
    = (n/2) * [4 + 2*n - 2]
    = (n/2) * (2*n + 2)
    = n * (n + 1)
0

 

Sum of first 20 Even numbers is: 420
00
Sum of first n terms of an A.P.(Arithmetic Progression)
= (n/2) * [2*a + (n-1)*d].....(i)
where, a is the first term of the series and d is
the difference between the adjacent terms of the series.

Here, a = 2, d = 2, applying these values to eq.(i), we get
Sum = (n/2) * [2*2 + (n-1)*2]
    = (n/2) * [4 + 2*n - 2]
    = (n/2) * (2*n + 2)
    = n * (n + 1)
2

Sum of first 20 Even numbers is: 420
00
Sum of first 20 Even numbers is: 420
05
                 Sum of first n even numbers = n * (n + 1).
737
                 Sum of first n even numbers = n * (n + 1).
770

                 Sum of first n even numbers = n * (n + 1).
9
Sum of first n terms of an A.P.(Arithmetic Progression)
= (n/2) * [2*a + (n-1)*d].....(i)
where, a is the first term of the series and d is
the difference between the adjacent terms of the series.

Here, a = 2, d = 2, applying these values to eq.(i), we get
Sum = (n/2) * [2*2 + (n-1)*2]
    = (n/2) * [4 + 2*n - 2]
    = (n/2) * (2*n + 2)
    = n * (n + 1)
6

 

                 Sum of first n even numbers = n * (n + 1).
9
Sum of first n terms of an A.P.(Arithmetic Progression)
= (n/2) * [2*a + (n-1)*d].....(i)
where, a is the first term of the series and d is
the difference between the adjacent terms of the series.

Here, a = 2, d = 2, applying these values to eq.(i), we get
Sum = (n/2) * [2*2 + (n-1)*2]
    = (n/2) * [4 + 2*n - 2]
    = (n/2) * (2*n + 2)
    = n * (n + 1)
8

                 Sum of first n even numbers = n * (n + 1).
9
Sum of first 20 Even numbers is: 420
0
Sum of first 20 Even numbers is: 420
14

Sum of first 20 Even numbers is: 420
9
Sum of first n terms of an A.P.(Arithmetic Progression)
= (n/2) * [2*a + (n-1)*d].....(i)
where, a is the first term of the series and d is
the difference between the adjacent terms of the series.

Here, a = 2, d = 2, applying these values to eq.(i), we get
Sum = (n/2) * [2*2 + (n-1)*2]
    = (n/2) * [4 + 2*n - 2]
    = (n/2) * (2*n + 2)
    = n * (n + 1)
6

Sum of first 20 Even numbers is: 420
9

Sum of first 20 Even numbers is: 420
9
Sum of first 20 Even numbers is: 420
19

Sum of first 20 Even numbers is: 420
9
                 Sum of first n even numbers = n * (n + 1).
618
                 Sum of first n even numbers = n * (n + 1).
707
Sum of first 20 Even numbers is: 420
23
Sum of first 20 Even numbers is: 420
24

Sum of first 20 Even numbers is: 420
9
Sum of first 20 Even numbers is: 420
8

                 Sum of first n even numbers = n * (n + 1).
9
Sum of first 20 Even numbers is: 420
4
Sum of first 20 Even numbers is: 420
29
Sum of first 20 Even numbers is: 420
30
                 Sum of first n even numbers = n * (n + 1).
770

                 Sum of first n even numbers = n * (n + 1).
9
Sum of first 20 Even numbers is: 420
33____02
Sum of first 20 Even numbers is: 420
35

________ 036 ________ 06 ________ 038

Sum of first 20 Even numbers is: 420
36
Sum of first 20 Even numbers is: 420
40

Sum of first 20 Even numbers is: 420
9
Sum of first n terms of an A.P.(Arithmetic Progression)
= (n/2) * [2*a + (n-1)*d].....(i)
where, a is the first term of the series and d is
the difference between the adjacent terms of the series.

Here, a = 2, d = 2, applying these values to eq.(i), we get
Sum = (n/2) * [2*2 + (n-1)*2]
    = (n/2) * [4 + 2*n - 2]
    = (n/2) * (2*n + 2)
    = n * (n + 1)
6

 

Sum of first n terms of an A.P.(Arithmetic Progression)
= (n/2) * [2*a + (n-1)*d].....(i)
where, a is the first term of the series and d is
the difference between the adjacent terms of the series.

Here, a = 2, d = 2, applying these values to eq.(i), we get
Sum = (n/2) * [2*2 + (n-1)*2]
    = (n/2) * [4 + 2*n - 2]
    = (n/2) * (2*n + 2)
    = n * (n + 1)
6

 

Sum of first 20 Even numbers is: 420
44

Python3




Sum of first 20 Even numbers is: 420
45

Sum of first 20 Even numbers is: 420
46

Sum of first 20 Even numbers is: 420
9

Sum of first 20 Even numbers is: 420
48

Sum of first 20 Even numbers is: 420
46

Sum of first 20 Even numbers is: 420
50
Sum of first 20 Even numbers is: 420
51

Sum of first 20 Even numbers is: 420
9
Sum of first 20 Even numbers is: 420
53
Sum of first 20 Even numbers is: 420
54
                 Sum of first n even numbers = n * (n + 1).
737

Sum of first 20 Even numbers is: 420
9
Sum of first 20 Even numbers is: 420
57
Sum of first 20 Even numbers is: 420
54
                 Sum of first n even numbers = n * (n + 1).
739

Sum of first 20 Even numbers is: 420
9
Sum of first 20 Even numbers is: 420
61
Sum of first 20 Even numbers is: 420
54
                 Sum of first n even numbers = n * (n + 1).
778

Sum of first 20 Even numbers is: 420
9

Sum of first 20 Even numbers is: 420
9
Sum of first 20 Even numbers is: 420
66

Sum of first 20 Even numbers is: 420
9
Sum of first 20 Even numbers is: 420
68
Sum of first 20 Even numbers is: 420
69______054
Sum of first 20 Even numbers is: 420
71

                 Sum of first n even numbers = n * (n + 1).
9
Sum of first 20 Even numbers is: 420
57
Sum of first 20 Even numbers is: 420
38
Sum of first 20 Even numbers is: 420
54
Sum of first 20 Even numbers is: 420
53

                 Sum of first n even numbers = n * (n + 1).
9

                 Sum of first n even numbers = n * (n + 1).
9
Sum of first 20 Even numbers is: 420
79

                 Sum of first n even numbers = n * (n + 1).
9
Sum of first 20 Even numbers is: 420
53____038
Sum of first 20 Even numbers is: 420
54
                 Sum of first n even numbers = n * (n + 1).
737

                 Sum of first n even numbers = n * (n + 1).
9
Sum of first 20 Even numbers is: 420
61
Sum of first 20 Even numbers is: 420
54
Sum of first 20 Even numbers is: 420
61
Sum of first 20 Even numbers is: 420
38
                 Sum of first n even numbers = n * (n + 1).
778

Sum of first 20 Even numbers is: 420
9
Sum of first 20 Even numbers is: 420
0
Sum of first 20 Even numbers is: 420
57

 

Sum of first 20 Even numbers is: 420
94

Sum of first 20 Even numbers is: 420
95
Sum of first 20 Even numbers is: 420
54
Sum of first 20 Even numbers is: 420
30

Sum of first 20 Even numbers is: 420
98
                 Sum of first n even numbers = n * (n + 1).
6
                 Sum of first n even numbers = n * (n + 1).
00
                 Sum of first n even numbers = n * (n + 1).
01
                 Sum of first n even numbers = n * (n + 1).
02
                 Sum of first n even numbers = n * (n + 1).
03

                 Sum of first n even numbers = n * (n + 1).
04
                 Sum of first n even numbers = n * (n + 1).
05

 

                 Sum of first n even numbers = n * (n + 1).
06

C#




                 Sum of first n even numbers = n * (n + 1).
07

                 Sum of first n even numbers = n * (n + 1).
613

                 Sum of first n even numbers = n * (n + 1).
77
                 Sum of first n even numbers = n * (n + 1).
10

 

                 Sum of first n even numbers = n * (n + 1).
618
                 Sum of first n even numbers = n * (n + 1).
619
                 Sum of first n even numbers = n * (n + 1).
13

 

Sum of first 20 Even numbers is: 420
9
Sum of first 20 Even numbers is: 420
2

Sum of first 20 Even numbers is: 420
9
                 Sum of first n even numbers = n * (n + 1).
70

Sum of first 20 Even numbers is: 420
9
                 Sum of first n even numbers = n * (n + 1).
707
Sum of first 20 Even numbers is: 420
4
Sum of first 20 Even numbers is: 420
5
Sum of first 20 Even numbers is: 420
4
Sum of first 20 Even numbers is: 420
7

Sum of first 20 Even numbers is: 420
9
Sum of first 20 Even numbers is: 420
8

                 Sum of first n even numbers = n * (n + 1).
9
Sum of first 20 Even numbers is: 420
4
                 Sum of first n even numbers = n * (n + 1).
1

 

                 Sum of first n even numbers = n * (n + 1).
9
                 Sum of first n even numbers = n * (n + 1).
3

                 Sum of first n even numbers = n * (n + 1).
9
                 Sum of first n even numbers = n * (n + 1).
5
                 Sum of first n even numbers = n * (n + 1).
6
Sum of first 20 Even numbers is: 420
4
                 Sum of first n even numbers = n * (n + 1).
8

Sum of first 20 Even numbers is: 420
00
Sum of first n terms of an A.P.(Arithmetic Progression)
= (n/2) * [2*a + (n-1)*d].....(i)
where, a is the first term of the series and d is
the difference between the adjacent terms of the series.

Here, a = 2, d = 2, applying these values to eq.(i), we get
Sum = (n/2) * [2*2 + (n-1)*2]
    = (n/2) * [4 + 2*n - 2]
    = (n/2) * (2*n + 2)
    = n * (n + 1)
0

 

Sum of first 20 Even numbers is: 420
00
Sum of first n terms of an A.P.(Arithmetic Progression)
= (n/2) * [2*a + (n-1)*d].....(i)
where, a is the first term of the series and d is
the difference between the adjacent terms of the series.

Here, a = 2, d = 2, applying these values to eq.(i), we get
Sum = (n/2) * [2*2 + (n-1)*2]
    = (n/2) * [4 + 2*n - 2]
    = (n/2) * (2*n + 2)
    = n * (n + 1)
2

Sum of first 20 Even numbers is: 420
00
Sum of first n terms of an A.P.(Arithmetic Progression)
= (n/2) * [2*a + (n-1)*d].....(i)
where, a is the first term of the series and d is
the difference between the adjacent terms of the series.

Here, a = 2, d = 2, applying these values to eq.(i), we get
Sum = (n/2) * [2*2 + (n-1)*2]
    = (n/2) * [4 + 2*n - 2]
    = (n/2) * (2*n + 2)
    = n * (n + 1)
4

                 Sum of first n even numbers = n * (n + 1).
9
Sum of first n terms of an A.P.(Arithmetic Progression)
= (n/2) * [2*a + (n-1)*d].....(i)
where, a is the first term of the series and d is
the difference between the adjacent terms of the series.

Here, a = 2, d = 2, applying these values to eq.(i), we get
Sum = (n/2) * [2*2 + (n-1)*2]
    = (n/2) * [4 + 2*n - 2]
    = (n/2) * (2*n + 2)
    = n * (n + 1)
6

 

                 Sum of first n even numbers = n * (n + 1).
9
Sum of first n terms of an A.P.(Arithmetic Progression)
= (n/2) * [2*a + (n-1)*d].....(i)
where, a is the first term of the series and d is
the difference between the adjacent terms of the series.

Here, a = 2, d = 2, applying these values to eq.(i), we get
Sum = (n/2) * [2*2 + (n-1)*2]
    = (n/2) * [4 + 2*n - 2]
    = (n/2) * (2*n + 2)
    = n * (n + 1)
8

                 Sum of first n even numbers = n * (n + 1).
9
Sum of first 20 Even numbers is: 420
0
Sum of first 20 Even numbers is: 420
1

Sum of first 20 Even numbers is: 420
9
Sum of first n terms of an A.P.(Arithmetic Progression)
= (n/2) * [2*a + (n-1)*d].....(i)
where, a is the first term of the series and d is
the difference between the adjacent terms of the series.

Here, a = 2, d = 2, applying these values to eq.(i), we get
Sum = (n/2) * [2*2 + (n-1)*2]
    = (n/2) * [4 + 2*n - 2]
    = (n/2) * (2*n + 2)
    = n * (n + 1)
6

 

Sum of first 20 Even numbers is: 420
9
Sum of first 20 Even numbers is: 420
19

Sum of first 20 Even numbers is: 420
9
                 Sum of first n even numbers = n * (n + 1).
618
                 Sum of first n even numbers = n * (n + 1).
707
Sum of first 20 Even numbers is: 420
23
                 Sum of first n even numbers = n * (n + 1).
57

Sum of first 20 Even numbers is: 420
9
Sum of first 20 Even numbers is: 420
8

                 Sum of first n even numbers = n * (n + 1).
9
Sum of first 20 Even numbers is: 420
4
Sum of first 20 Even numbers is: 420
9

                 Sum of first n even numbers = n * (n + 1).
9

                 Sum of first n even numbers = n * (n + 1).
9
                 Sum of first n even numbers = n * (n + 1).
65
Sum of first 20 Even numbers is: 420
2
                 Sum of first n even numbers = n * (n + 1).
67

Sum of first 20 Even numbers is: 420
4
Sum of first 20 Even numbers is: 420
38
Sum of first 20 Even numbers is: 420
6
                 Sum of first n even numbers = n * (n + 1).
71

Sum of first 20 Even numbers is: 420
9
Sum of first n terms of an A.P.(Arithmetic Progression)
= (n/2) * [2*a + (n-1)*d].....(i)
where, a is the first term of the series and d is
the difference between the adjacent terms of the series.

Here, a = 2, d = 2, applying these values to eq.(i), we get
Sum = (n/2) * [2*2 + (n-1)*2]
    = (n/2) * [4 + 2*n - 2]
    = (n/2) * (2*n + 2)
    = n * (n + 1)
6

Sum of first n terms of an A.P.(Arithmetic Progression)
= (n/2) * [2*a + (n-1)*d].....(i)
where, a is the first term of the series and d is
the difference between the adjacent terms of the series.

Here, a = 2, d = 2, applying these values to eq.(i), we get
Sum = (n/2) * [2*2 + (n-1)*2]
    = (n/2) * [4 + 2*n - 2]
    = (n/2) * (2*n + 2)
    = n * (n + 1)
6

 

                 Sum of first n even numbers = n * (n + 1).
75

PHP




                 Sum of first n even numbers = n * (n + 1).
76

                 Sum of first n even numbers = n * (n + 1).
77

                 Sum of first n even numbers = n * (n + 1).
70

 

Sum of first 20 Even numbers is: 420
2

                 Sum of first n even numbers = n * (n + 1).
70

                 Sum of first n even numbers = n * (n + 1).
81
Sum of first 20 Even numbers is: 420
5____183
                 Sum of first n even numbers = n * (n + 1).
84

Sum of first 20 Even numbers is: 420
8

Sum of first 20 Even numbers is: 420
9
                 Sum of first n even numbers = n * (n + 1).
87
                 Sum of first n even numbers = n * (n + 1).
88

Sum of first 20 Even numbers is: 420
9
                 Sum of first n even numbers = n * (n + 1).
90
                 Sum of first n even numbers = n * (n + 1).
91

 

Sum of first 20 Even numbers is: 420
9
                 Sum of first n even numbers = n * (n + 1).
3

Sum of first 20 Even numbers is: 420
9
                 Sum of first n even numbers = n * (n + 1).
5
                 Sum of first n even numbers = n * (n + 1).
6
                 Sum of first n even numbers = n * (n + 1).
97
                 Sum of first n even numbers = n * (n + 1).
98
                 Sum of first n even numbers = n * (n + 1).
97
Sum of first n terms of an A.P.(Arithmetic Progression)
= (n/2) * [2*a + (n-1)*d].....(i)
where, a is the first term of the series and d is
the difference between the adjacent terms of the series.

Here, a = 2, d = 2, applying these values to eq.(i), we get
Sum = (n/2) * [2*2 + (n-1)*2]
    = (n/2) * [4 + 2*n - 2]
    = (n/2) * (2*n + 2)
    = n * (n + 1)
00
                 Sum of first n even numbers = n * (n + 1).
83
                 Sum of first n even numbers = n * (n + 1).
770
                 Sum of first n even numbers = n * (n + 1).
97
Sum of first n terms of an A.P.(Arithmetic Progression)
= (n/2) * [2*a + (n-1)*d].....(i)
where, a is the first term of the series and d is
the difference between the adjacent terms of the series.

Here, a = 2, d = 2, applying these values to eq.(i), we get
Sum = (n/2) * [2*2 + (n-1)*2]
    = (n/2) * [4 + 2*n - 2]
    = (n/2) * (2*n + 2)
    = n * (n + 1)
04

                 Sum of first n even numbers = n * (n + 1).
9
                 Sum of first n even numbers = n * (n + 1).
90
Sum of first n terms of an A.P.(Arithmetic Progression)
= (n/2) * [2*a + (n-1)*d].....(i)
where, a is the first term of the series and d is
the difference between the adjacent terms of the series.

Here, a = 2, d = 2, applying these values to eq.(i), we get
Sum = (n/2) * [2*2 + (n-1)*2]
    = (n/2) * [4 + 2*n - 2]
    = (n/2) * (2*n + 2)
    = n * (n + 1)
07
                 Sum of first n even numbers = n * (n + 1).
87
                 Sum of first n even numbers = n * (n + 1).
770

 

                 Sum of first n even numbers = n * (n + 1).
9
Sum of first n terms of an A.P.(Arithmetic Progression)
= (n/2) * [2*a + (n-1)*d].....(i)
where, a is the first term of the series and d is
the difference between the adjacent terms of the series.

Here, a = 2, d = 2, applying these values to eq.(i), we get
Sum = (n/2) * [2*2 + (n-1)*2]
    = (n/2) * [4 + 2*n - 2]
    = (n/2) * (2*n + 2)
    = n * (n + 1)
2

                 Sum of first n even numbers = n * (n + 1).
9
                 Sum of first n even numbers = n * (n + 1).
87
Sum of first n terms of an A.P.(Arithmetic Progression)
= (n/2) * [2*a + (n-1)*d].....(i)
where, a is the first term of the series and d is
the difference between the adjacent terms of the series.

Here, a = 2, d = 2, applying these values to eq.(i), we get
Sum = (n/2) * [2*2 + (n-1)*2]
    = (n/2) * [4 + 2*n - 2]
    = (n/2) * (2*n + 2)
    = n * (n + 1)
14

Sum of first 20 Even numbers is: 420
9
Sum of first n terms of an A.P.(Arithmetic Progression)
= (n/2) * [2*a + (n-1)*d].....(i)
where, a is the first term of the series and d is
the difference between the adjacent terms of the series.

Here, a = 2, d = 2, applying these values to eq.(i), we get
Sum = (n/2) * [2*2 + (n-1)*2]
    = (n/2) * [4 + 2*n - 2]
    = (n/2) * (2*n + 2)
    = n * (n + 1)
6

 

Sum of first 20 Even numbers is: 420
9
Sum of first n terms of an A.P.(Arithmetic Progression)
= (n/2) * [2*a + (n-1)*d].....(i)
where, a is the first term of the series and d is
the difference between the adjacent terms of the series.

Here, a = 2, d = 2, applying these values to eq.(i), we get
Sum = (n/2) * [2*2 + (n-1)*2]
    = (n/2) * [4 + 2*n - 2]
    = (n/2) * (2*n + 2)
    = n * (n + 1)
8

Sum of first 20 Even numbers is: 420
9
Sum of first 20 Even numbers is: 420
0
                 Sum of first n even numbers = n * (n + 1).
6
Sum of first 20 Even numbers is: 420
4
                 Sum of first n even numbers = n * (n + 1).
7311
                 Sum of first n even numbers = n * (n + 1).
7312______2737
                 Sum of first n even numbers = n * (n + 1).
84
Sum of first 20 Even numbers is: 420
01
                 Sum of first n even numbers = n * (n + 1).
6
                 Sum of first n even numbers = n * (n + 1).
737
Sum of first 20 Even numbers is: 420
38
                 Sum of first n even numbers = n * (n + 1).
7319

Làm cách nào để in tổng các số chẵn trong C?

Chương trình. Viết chương trình tìm tổng các số chẵn bằng ngôn ngữ C. .
#include .
int chính ()
int i, n, tổng=0;
printf("Nhập số bất kỳ. ");
scanf("%d", &n);
for(i=2; i<=n; i+=2)

Làm thế nào để tìm tổng của n số chẵn đầu tiên trong C?

Để tìm tổng của các số chẵn, chúng ta cần lặp qua các số chẵn từ 1 đến n. Khởi tạo một vòng lặp từ 2 đến N và tăng 2 trên mỗi lần lặp. Cấu trúc vòng lặp sẽ giống như for(i=2; i<=N; i+=2). Bên trong thân vòng lặp thêm giá trị trước đó của tổng với i i. e. tổng = tổng + tôi

Từ 1 đến n có bao nhiêu số chẵn?

10 là số chẵn nhỏ nhất có hai chữ số. Có tổng 50 các số chẵn từ 1 đến 100. 2 là số nguyên tố chẵn duy nhất. Các số chia hết cho 2 là số chẵn.

Làm cách nào để in các số chẵn từ 1 đến 100 trong C?

Viết chương trình C in tất cả các số chẵn từ 1 đến 100. .
int main(){
int tôi;
cho (i=1;i<=100;i++){
nếu(i%2==0){
printf("%d\n",i);