( 1+2+3+4+5+...+2015+2016) x ( 9x11-100+1)
= ( 1+2+3+4+5+...+2015+2016) x 0
=> 0
Vì 9*11 - 100 + 1 = 0, mà số nào nhân với 0 cũng bằng 0 => (1 + 2 + 3 + 4 + 5 + ..... + 2015 + 2016)*(9*11 - 100 + 1)= 0
Tính: ( 1 + 2 + 3 + 4 + 5 +.............+ 2015 + 2016 ) x ( 9 x 11 - 100 + 1 )
TÍNH (1 +2 + 3 + 4 + 5 +...+ 2015 + 2016 ) x (9 x 11 - 100 + 1 )
[ 1+2+3+4+5+...+2015+2016] nhân với [9 nhân 11 trừ 100+1]=...
1+2+3+4+5+...+2015+2016 + ( 9 *11 - 100+1) = _________?
(1 + 2+ 3 ......... + 2015 + 2016 ) x ( 9 x 11 - 100 + 1)
(1+2+3+4+5+...+2015+2106)*(9*11-100+1)=...
(1+2+3+4+5+...+2015+2016)x(9x1-100+1)=?
(2/3 + 3/4 + 4/5 +... + 2016/2017) x (1/2 + 2/3 + 3/4 + ...+ 2015/2016) - (1/2 + 2/3 + 3/4 +...+2015/2016) x (2/3 + 3/4 + 4/5 +...+2015/2016)
(2/3 + 3/4 + 4/5 + .........+ 2016 /2017 ) x ( 1/2 + 2/3 + 3/4 + ......+ 2015 /2016) - ( 1/2 + 2/3 + 3/4 + ........2016 /2017 ) x 2/3 + 3/4 + 4/5 + .....+ 2015/2016)
