Carcass wrote:
Which of the following is equivalent to
a100−b100a50−b50 for all values of a and b for which the expression is defined?
(A) a^2+b^2
(B) a^2-b^2
(C) a^50+b^50
(D) a^50-b^50
(E) (ab)^2
Kudos for the right answer and explanation
Question part of the project GRE Quantitative Reasoning Daily Challenge - (2021) EDITIONGRE - Math BookThe numerator has a nice
difference of squares, which can be factored
Note: a^100 = (a^50)²
So, (
a^100 - b^100)/(a^50 - b^50) = (
a^50 + b^50)(
a^50 - b^50)/(a^50 - b^50)
= a^50 + b^50
Answer: C