Given that f(x) = -x + 4 and g(x) = -2x - 3, solve for f(g(x)) when x = 2.
Solution:
g(x) = - 2x - 3 ….. (1)
f(x) = - x + 4 ….. (2)
f(g(x)) can be written as (fog)(x) which is a composite function.
f(g(x)) takes the input values of g(x).
I.e., substituting equation (1) in x which is present in equation (2)
f(g(x)) = f(-2x - 3)
f(g(x)) = - (- 2x - 3) + 4
f(g(x)) = 2x + 3 + 4
f(g(x)) = 2x + 7
Now substitute x = 2 in f (g(x))
f(g(x)) = 2 (2) + 7
So we get
f(g(x)) = 4 + 7 = 11
Therefore, f(g(x)) when x = 2 is 11.
Given that f(x) = -x + 4 and g(x) = -2x - 3, solve for f(g(x)) when x = 2.
Summary:
Given that f(x) = -x + 4 and g(x) = -2x - 3, f(g(x)) when x = 3 is 11.
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