x-3-8x-2-7-factorise-it-

Question Number 26638 by shiv15031973@gmail.com last updated on 27/Dec/17

x^{3} - {8 x}^{2} + 7 factorise it .

Answered by prakash jain last updated on 27/Dec/17

x^{3} - 8 x^{2} + 7

= x^{3} - x^{2} - 7 x^{2} + 7

= x^{2} (x - 1) - 7 (x^{2} - 1)

= x^{2} (x - 1) - 7 (x - 1) (x + 1)

= (x - 1) (x^{2} - 7 x - 7)

Commented by kaivan.ahmadi last updated on 27/Dec/17

so good