Question

factorise x3-3x2-9x-5​

Answer 1

Question:

Factorise x³-3x²-9x-5

Answer:

The factors are (x + 1) (x - 5) (x+ 1)

x = -1 , -1 and -5

Step by step explanation:

x³-3x²-9x-5

= x³ + x2 - 4x² - 4x - 5x -5

= x²(x + 1) - 4x ( x + 1) - 5(x + 1)

= (x + 1) (x² - 4x - 5)

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

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

x + 1 = 0 x - 5 = 0 x + 1 = 0

x = -1 x = -5 x = -1

Conclusion:

I hope u understood.

Answer 2

Step-by-step explanation:

=x³-3x²-9x-5

=(x+1) (x²-4x-5)+0

=(x+1) (x²-5x+x-5)

=(x+1) [x (x-5) + 1 (x-5) ]

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

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