Question

Factorise..(x+y-z)^3 +(x-y+z)^3 -8x^3

Answer 1

-6x(x+y-z)(x-y+z)

hint: (x+(y-z))(z-(y-z)) = x^2 - (y-z)^2
(x+(y-z))^3 + (x-(y-z))^3 = (x+y-z)(x^2 - (y-z)(y+z) + (y-z)^2)