Question

Expanding Brackets when cubed eg

(x - 5)3 Answer given is xcubed -15xsquared + 75x -125 How do I work this? I can do two brackets but having trouble with the three brackets. Thanks

Answer 1

Solve like this - (x-5)^3
= (x-5)(x-5)^2
= (x-5) ( x^2 -10x + 25)
= x^3 -15x^2 + 75 - 125

Hope this helped