19 fand g are functions such that
12
(c)
and g(x)=3(2x + 1)
(a) Find g(5)
(b) Find gf(9)
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Answer:
(a) 33
(b) 27
(c) 1/2
Step-by-step explanation:
(a)
g(x) = 3(2x + 1)
g(5) = 3(2 * 5 + 1)
g(5) = 3(10 + 1)
g(5) = 3(11)
g(5) = 33
(b)
[tex] f(x) = \dfrac{12}{\sqrt{x}} [/tex]
[tex] f(9) = \dfrac{12}{\sqrt{9}} [/tex]
[tex] f(9) = \dfrac{12}{3} [/tex]
[tex] f(9) = 4 [/tex]
g(f(9)) = g(4) = 3(2(4) + 1)
g(f(9)) = 3(9)
g(f(9)) = 27
(c)
[tex] g(x) = 3(2x + 1) [/tex]
[tex] y = 3(2x + 1) [/tex]
[tex] x = 3(2y + 1) [/tex]
[tex] 2y + 1 = \dfrac{x}{3} [/tex]
[tex] 2y = \dfrac{x}{3} - 1 [/tex]
[tex] y = \dfrac{x}{6} - \dfrac{1}{2} [/tex]
[tex] g^{-1}(x) = \dfrac{x}{6} - \dfrac{1}{2} [/tex]
[tex] g^{-1}(6) = \dfrac{6}{6} - \dfrac{1}{2} [/tex]
[tex] g^{-1}(6) = 1 - \dfrac{1}{2} [/tex]
[tex] g^{-1}(6) = \dfrac{1}{2} [/tex]