Question

factorise x³+13²+32x+20

Answer 1

x^3+13x^2+32x+20

=x^3+10x^2+3x^2+30x+2x+20

=x^2 (x+10)+3x (x+10)+2 (x+10)

=(x+10)(x^2+3x+2)

=(x+10)(x^2+x+2x+2)

=(x+10)[x (x+1)+2 (x+1)]

=(x+10)(x+1)(x+2)

Answer 2

x^3+13x^2+32x+20= x^3 + x^2+ 12x^2 + 12x + 20x + 20

=x^2(x+1) + 12x(x+1) +20(x+1)

=(x^2 + 12x + 20)(x+1)

=(x^2 + 10x + 2x + 20)(x + 1)

={x(x + 10) + 2(x + 10)}(x + 1)

=(x+1)(x+2)(x+10)