Factor the expression below.
9x^2 - 1
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Answer:
C
Step-by-step explanation:
Given
9x² - 1 ← is a difference of squares and factors in general as
a² - b² = (a - b)(a + b), thus
9x² - 1
= (3x)² - 1² = (3x - 1)(3x + 1) → C