You need the Binomial Theorem:
(a+b)^n = a^n + n a^(n-1) b + ...
So, you have
(3x-2)^3
= (3x)^3 - 3(3x)^2(2) + 3(3x)(2^2) - 2^3
= 27x^3 - 54x^2 + 36x - 8
(4x+5)^2
= (4x)^2 + 2(4x)(5) + 5^2
= 16x^2 + 40x + 25
Subtract them to get
27x^3 - 70x^2 - 4x - 33
Simplify (3x-2)^3 - (4x+5)^2
Can you show it step-by-step please
1 answer