Question

Find the domain for which the functions f (x) = 2x2 – 1 and g (x) = 1 – 3x are equal.

Answer 1

f(x) = g(x)

2x^2 - 1 = 1 - 3x

2x^2 + 3x - 1 = 1

2x^2 + 3x - 2 = 0

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

x = - 3/4 ± √(9/16 + 1)

x1 = -2

x2 = 0.5

L = {-2 ; 0.5}