Question

Rút gọn biểu thức :

(x-y+z)² + (z-y)² + 2.(x-y+z).(y-z)

Answer 1

=(x-y+z)²  + 2.(x-y+z).(y-z)+ (y-z)²=(x-y+z+y-z)²=x²

Answer 2

 

(x-y+z)² + (z-y)² + 2.(x-y+z).(y-z)

= (x-y+z)² + (y-z)² + 2.(x-y+z).(y-z)

=[(x-y+z)+(y-z)]²

=(x-y+z+y-z)²

=x²

Answer 3

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