If g(x) = x ^2 + 2x, x ≥ 0, find g ^-1(3)....?

Question

If g(x) = x ^2 + 2x, x ≥ 0, find g ^-1(3).

a. g^ -1(3) = -3
b. g ^-1(3) = -1
c. g ^-1(3) = 1
d. g ^-1(3) = 3
e. g^ -1(3) = 5

Answer 1

You've asked the previous four questions on YOUR homework, why don't you just list it all in one question with the subject line "please do my homework?"

Answer 2

A-3

Answer 3

Let's find a non-negative x such that x^2 + 2x = 3

x^2 + 2x = 3 // -3

x^2 + 2x - 3 = 0 // Completing the square

x^2 + 2x + 1 - 1 - 3 = 0

(x + 1)^2 - 4 = 0

(x + 1)^2 - 2^2 = 0

(x + 1 - 2)(x + 1 + 2) = 0

(x - 1)(x + 3) = 0

Choose x=1 because -3 < 0

g^-1(3) - 1

The correct answer is c.