Question

Thực hiện phép tính: (x-1)^2+(x+1)^2

Answer 1

\(\left(x-1\right)^2+\left(x+1\right)^2\\ =x^2-2x+1+x^2+2x+1\\ =x^2+x^2-2x+2x+1+1\\ =2x^2+2\)

Answer 2

\(\left(x-1\right)^2+\left(x+1\right)^2\)

\(=x^2-2x+1+x^2+2x+1\)

\(=2x^2+2\)

\(=2\left(x^2+1\right)\)

Answer 3

\(\left(x-1\right)^2+\left(x+1\right)^2=\left(x^2-2x+1\right)+\left(x^2+2x+1\right)=x^2-2x+1+x^2+2x+1=2x^2+2\)