Question

Factorise:27-125a3-135a+225a2​

Answer 1

(a-b)^3 = a^3 - b^3 -3*a^2*b + 3* a* b^2

27 - 124a3 - 135a + 225a2

= 3^ 3 - (5a)^3 - 3* 3^2* 5a + 3* 3* (5a)^2

= (3-5a)^3

= (3-5a)(3-5a)(3-5a)