Given:
f(x) = x^2 + 3x - 2
(a) f(-1)
lets substitute x = -1 to the given equation.
f(x) = x^2 + 3x - 2
f(x=2) = 1^2 + 3(-1) - 2
= 1 - 3 - 2
= -4
(b) f(x+5)
lets substitute x + 5 to the given equation.
f(x) = x^2 + 3x - 2
f(x+5) = (x + 5)^2 + 3(x + 5) - 2
= (x^2 + 5x + 5x + 25) + 3x + 15 - 2
= x^2 + 10x + 25 + 3x + 15 - 2
= x^2 + 13x + 38
(c) f(-x)
lets substitute x-----> -x to the given equation.
f(x) = x^2 + 3x - 2
f(-x) = (-x)^2 + 3(-x) - 2
= x^2 - 3x - 2
Therefore the corresponding answers are:
f(-1) = -4
f(x + 5) = x^2 + 13x + 38
f(-x) = x^2 - 3x - 2