16Hit1600
Advanced MathMediumSquare root of a perfect-square trinomial

Advanced Math practice question

For x > 0, which expression is equal to √(x² + 2x + 1)?

  1. A. x + 1Correct
  2. B. x − 1
  3. C. x + √(2x) + 1
  4. D. x² + 1

Answer: A. x + 1

x² + 2x + 1 = (x + 1)², and for x > 0 its square root is x + 1.

Why the other answers are wrong

B. x − 1
(x − 1)² = x² − 2x + 1, the wrong middle sign.
C. x + √(2x) + 1
A square root does not distribute over addition.
D. x² + 1
x² + 1 is not the square root of anything here; the root halves the degree.

More Advanced Math questions

Not affiliated with the College Board. SAT is a trademark of the College Board.