Help an question that I can´t even understand........

Question

If the expression f²+g⁴−2f+1 is rewritten in the form a²+(g²)², what must be the value of a?

 

choices

 

A. f - 2  B. f - 1  C. f + 1 D.  f + g - 1

 

Answer 1

Since (g^2)^2 is the same as g^4, we can focus on what's left: f^2 - 2f +1. When we factor this, we get (f - 1)^2. So the a in a^2 is f-1. The purpose of this problem is to get you to get rid of what you don't need and to see that the same thing can be expressed in different ways.

Answer 2

C) f+1

f^2 + g^4 -2f-+1

= f^2 + 2f + 1 + (g^2)

(f+1)^2 +(g^2)^2

a^2 = (f+1)^2

a = f+1