Question

factorise x³+13x²+32x+20
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Answer 1

Answer:

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

Step-by-step explanation:

Q. x³+13x²+32x+20

p(1) =(1)³+13(1²) +32(1) +20

=1+13+32+20

=66

p(-1) = (-1)³+13(-1)²+32(-1)+20

= -1+13-32+20

= -20+20

= 0

p(-1) =0

therefore, x+1 is the factor of p(x)

p(x)/x+1=x²+12x+20

x²+12x+20

_____________

x+1 | x³+13x²+32x+20

x³+x²

______________

12x²+32

12x²+12x

________________

20x+20

20x+20

_________________

0

x²+12x+20

=x²+10x+2x+20

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

= (x+2) (x+10)

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