Question

What are the roots of the function f(x) = x2 + 2x – 1? a. x = ± √ _ 2 b. x = − 1 ± √ _ 2 c. x = 2 ± √ _ 2 d. x = 1 ± √ _ 2

Answer 1

Step-by-step explanation:

Root of the function, where y = 0

f(x) = x² + 2x - 1

0 = x² + 2x - 1

x² + 2x - 1 = 0

x² + 2x = 1

x² + 2x + 1 = 1 + 1

(x + 1)² = 2

x + 1 = ±√2

x = -1 ± √2

Roots → x = -1 ± √2