Question

Answer 1

a) \(3x\left(x^2-5x+7\right)=3x^3-15x+21x\)

b) \(-2xy\left(2x^3+5x-1\right)=-4x^4y-10x^2y+2xy\)

c) \(\left(x+4\right)\left(-x^2+6x+5\right)=-x^3-10x^2-19x+20\)