Question

* Tính hộ mình cái:

a) \(\left(a+b+c\right)^2=\)

b) \(\left(a+b+c\right)^3=\)

c) \(\left(a-b-c\right)^2=\)

d) \(\left(a-b-c\right)^3=\)

Giúp mình nha!!!

Answer 1

a, \(\left(a+b+c\right)^2=a^2+b^2+c^2+2ab+2bc+2ac\)

b,\(\left(a+b+c\right)^3=\left[\left(a+b\right)+c\right]^3=\left(a+b\right)^3+3\left(a+b\right)^2.c+3\left(a+b\right).c^2+c^3\)

( Bn tự nhân nốt ra nhé )

c,\(\left(a-b-c\right)^2=a^2+b^2+c^2-2ab-2ac+2bc\)

\(d,\left(a-b-c\right)^3=\left[\left(a-b\right)-c\right]^3=\left(a-b\right)^3-3\left(a-b\right)^2.c+3\left(a-b\right).c^2+c^3\)

( Bn cũng tự nhân nốt ra nhé )