if f(x)= (x-2)^2 (2x+1) what is f(x+1) please show step by step

Question

i have the answer which is f(x+1)= (x-1)^2 (2x+3) but i don't understand how they got it

Answer 1

You must REPLACE x with x+1

f(x+1) = (x+1-2)^2 ( 2(x+1)+1) =

(x-1)^2 [ 2x + 2 + 1] =

(x-1)^2 ( 2x + 3)