Question

Rút gọn:

a.x(x+1)+(x-2)(x-3)

b.(x+3)^2(x-2)(x+2)

Answer 1

\(a,=x^2+x+x^2-5x+6=2x^2-4x+6\\ b,Sửa:\left(x+3\right)^2+\left(x-2\right)\left(x+2\right)=x^2+6x+9+x^2-4=2x^2+6x+5\)

Answer 2

\(a,x\left(x+1\right)+\left(x-2\right)\left(x-3\right)=\left(x^2+x\right)+\left(x^2-2x-3x+6\right)=x^2+x+x^2-5x+6=2x^2-4x+6\)

\(b,\left(x+3\right)^2\left(x-2\right)\left(x+2\right)=\left(x^2+6x+9\right)\left(x^2-4\right)=x^2\left(x^2+6x+9\right)-4\left(x^2+6x+9\right)=x^4+6x^3+9x^2-4x^2-24x-36=x^4+6x^3+5x^2-24x-36\)