Question

25. Factorise x3 - 3x2 - 9x - 5.​

Answer 1

Step-by-step explanation:

Factorise x3 - 3x2 - 9x - 5.

Answer 2

Step-by-step explanation:

x³-3x²-9x-6 +1

x³-3(x²+3x+2)+1

x³+1-3((x+1)(x+2))

(x+1)(x²-x+1) -3(x+1)(x+2)

because x³+1³=(x+1)(x²-x+1)

(x+1)(x2-x+1-3(x+2))

(x+1)(x²-x+1-3x-6)

(x+1)(x²-4x-5)

(x+1)(x2-5x+x-5)

(x+1)(x(x-5)+1(x-5))

(x+1)(x+1)(x-5)