CEMC Fermat, 2020

Algebra Difficulty 1.1 Junior Find the answer Canada

For every real number $x$ , the expression $(x+1)^2 - x^2$ is equal to

$2x+1$
$2x-1$
$(2x+1)^2$
$-1$
$x+1$

Your answer

A number or a short expression. Fractions can be typed as 3/2, and spacing doesn't matter.

Solution

Expanding and simplifying, $(x+1)^2 - x^2 = (x^2 + 2x + 1) - x^2 = 2x + 1$ .

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