Let f(x) = x - 2 and g(x) = x2 - 7x - 9. Find f(g(-1))
Solution:
Given that:
f(x) = x − 2 ---------- (1)
g(x) = x2 − 7x − 9 ----------- (2)
Both f(x) and g(x) are the function of x and thus depend on x.
We have to find the composite function f(g(x))
f(g(x)) = {g(x)} - 2
f(g(x)) = (x2 − 7x − 9) - 2 [From (1) and (2)]
f(g(x)) = x2 − 7x − 11
Now let us solve this for x = -1.
f(g(-1)) = (-1)2 − 7(-1) − 11
f(g(-1)) = 1 + 7 -11
f(g(-1)) = -3
Thus, if f(x) = x − 2 and g(x) = x2 − 7x − 9, then f(g(-1)) is -3.
Let f(x) = x - 2 and g(x) = x2 - 7x - 9. Find f(g(-1))
Summary:
Let f(x) = x - 2 and g(x) = x2 - 7x - 9, then f(g(-1)) is -3.
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