Question

Rút gọn :

(1+2x)² + 2(1+2x)(x-1)+(x-1)²

Answer 1

\(\left(1+2x\right)^2+2\left(1+2x\right)\left(x-1\right)+\left(x-1\right)^2=\left(1+2x+x-1\right)^2=\left(3x\right)^2=9x^2\)