Algebraic Expansion and Simplification

Questions that require expanding brackets or applying algebraic identities (e.g., difference of squares) to simplify a variable expression to a simpler form.

turkey-yks 2010 Q4 View

$$( a + 1 ) ^ { 2 } - ( a - 1 ) ^ { 2 }$$
Which of the following is this expression equal to?
A) a
B) $2 a$
C) $3 a$
D) 4 a
E) $5 a$