Question

factorise x3+13x2+3x+20

Answer 1

Step-by-step explanation:

let p(x)= x3 + 13x2+32x+20

p(-1)=-1+13-32+20=-33+33=0

on dividing p(x) by( x+1) we get,

p(x) ( x+1)= x2 +12x+20

thus, x3+13x2+32x+20=(x+1) (x2+12x+20)

(x+1) ( x2+10x +2x+20)

( x+1) (x2+10x+2x+20)

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

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

hence,x3+13x2+32x+20=(x+1)(x+2)(x+10