\(a,=x^2+4x+4+x^2-9=2x^2+4x-5\\ b,=x^2-8x+16-x^2-x=-9x+16\\ c,=x^2-14x+49-x^2-6x-9=-20x+40\\ d,=\left(2x+1-3x+2\right)\left(2x+1+3x-2\right)=\left(3-x\right)\left(5x-1\right)=-5x^2+16x-3\)
Đúng 5
Bình luận (0)