Nếu Có Thể
21/03/2017 at 17:12-
Trịnh Đức Phát 22/03/2017 at 12:39We have : A = 1.2 + 2.3 + 3.4 + ...... + 100.101
=> 3A = 1.2.3 - 1.2.3 + 2.3.4 - 2.3.4 + ....... + 99.100.101
=> 3A = 99.100.101
=> A = 99.100.101/3
=> A = 333300
Nếu Có Thể selected this answer. -
→இے๖ۣۜQuỳnh 22/03/2017 at 20:15B = 1 + 2 + 3 + ...... + 100
B is numbered as:
100 - 1 + 1 = 100 (số)
Total B is:
(100 x 101) : 2 = 5050
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→இے๖ۣۜQuỳnh 22/03/2017 at 20:14
C = 12 + 22 + 32 + ...... + 1002
= 1.1 + 2.2 + 3.3 + ...... + 100.100
= 1.(2 - 1) + 2.(3 - 1) + 3.(4 - 1) + ...... + 100.(101 - 1)
= 1.2 - 1 + 2.3 - 2 + 3.4 - 3 + ....... + 100.101 - 100
= (1.2 + 2.3 + 3.4 + ...... + 100.101) - (1 + 2 + 3 + ...... + 100)
From the calculated results of A and B we should compute
C = 333300 - 5050
C = 328250
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Nguyễn Việt Hoàng 21/03/2017 at 17:16We have : A = 1.2 + 2.3 + 3.4 + ...... + 100.101
=> 3A = 1.2.3 - 1.2.3 + 2.3.4 - 2.3.4 + ....... + 99.100.101
=> 3A = 99.100.101
=> A = 99.100.101/3
=> A = 333300
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Nguyễn Xuân Sáng 22/03/2017 at 12:26\(B=1+2+3+...+100\)
Total B has:
\(\dfrac{100-1}{1}+1=100\) (number)
Total B is:
\(\dfrac{\left(100+1\right)\cdot100}{2}=5050\)
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Nguyễn Việt Hoàng 21/03/2017 at 17:19
C = 12 + 22 + 32 + ...... + 1002
= 1.1 + 2.2 + 3.3 + ...... + 100.100
= 1.(2 - 1) + 2.(3 - 1) + 3.(4 - 1) + ...... + 100.(101 - 1)
= 1.2 - 1 + 2.3 - 2 + 3.4 - 3 + ....... + 100.101 - 100
= (1.2 + 2.3 + 3.4 + ...... + 100.101) - (1 + 2 + 3 + ...... + 100)
From the calculated results of A and B we should compute
C = 333300 - 5050
C = 328250
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Nguyễn Việt Hoàng 21/03/2017 at 17:17
B = 1 + 2 + 3 + ...... + 100
B is numbered as:
100 - 1 + 1 = 100 (số)
Total B is:
(100 x 101) : 2 = 5050
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Trịnh Đức Phát 22/03/2017 at 12:38
B = 1 + 2 + 3 + ...... + 100
B is numbered as:
100 - 1 + 1 = 100 (số)
Total B is:
(100 x 101) : 2 = 5050