Question

Áp dụng hằng đẳng thức:

\(x^2-y^2=...\)

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

ai k mk mk k lại

Answer 1

\(x^2-y^2=\left(x+y\right)\left(x-y\right)\)

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

ai k mk mk k lại

Answer 2

x²-y²=(a-y)(x+y) ;  

Answer 3

a) ( x+y)x(x-y)

b) a^2+2ab+b^2