Question

thực hiện phép tính một cách hợp lý:

(1+2+3+..........+2009+2010)*(1176*72+15*1176-1176*87)=?

 

Answer 1

= (1+2+3+..........+2009+2010)*(1176*[72+15-87])

=(1+2+3+...........+2009+2010)*(1176*0)

=(1+2+3+...........+2009+2010)*0

=0

Answer 2

\(=\left(1+2+3+...+2010\right)\cdot\left(1176\cdot72+15\cdot1176-1176\cdot87\right)\)

\(=\left(1+2+3+...+2010\right)\cdot\left(1176\cdot72-1176\cdot\left(87-15\right)\right)\)

\(=\left(1+2+3+...+2010\right)\cdot\left(1176\cdot72-1176\cdot72\right)\)

\(=\left(1+2+3+...+2010\right)\cdot0=0\)