The Goal

Simplify the rational expression:

The Mistake

Find the algebra mistake:

Need a hint? Look carefully at the red part of the algebra:

The Correction

An Explanation

Care is needed when multiplying out expressions. The parentheses indicate that both x² and 1 must be multiplied by 2. The two 2s must be multiplied together in the term 2x(2x). Slow down and check your work!
(Tempted to cancel the (x² + 1) in the numerator and one of the (x² + 1) factors in the denominator? You cannot! To cancel a factor it needs to be a common factor of the entire numerator and the entire denominator. In this case (x² + 1) is not a common factor of the entire numerator)