For every real number x, the expression (x+1)2−x2 is equal to
2x+1 2x−1 (2x+1)2 −1 x+1
A number or a short expression. Fractions can be typed as 3/2, and spacing doesn't matter.
Solution
Expanding and simplifying, (x+1)2−x2=(x2+2x+1)−x2=2x+1.
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