Question

Rút gọn biểu thức sau...

(x+y)^2+(x-y)^2-2(x+y)(x-y)

Answer 1

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

\(=x^2+2xy+y^2+x^2-2xy+y^2-2x^2+2y^2\)

\(=4y^2\)

Answer 2

= x²+2xy+y²+x²-2xy+y²-2(x²-y²)

=(x²+x²)+(2xy-2xy)+(y²+y²)-2x²+2y²

=2x²+2y²-2x²+2y²

=4y²

Answer 3

\(\left(x+y\right)^2+\left(x-y\right)^2-2\left(x+y\right)\left(x-y\right)=\left(x+y-x+y\right)^2=\left(2y\right)^2=4y^2\)