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Composite Functions

Let's see what happens when we combine functions.

a) When $-1$ is the input, what is the final output?

b) When $x$ is the input, what is the final output?

c) When $x$ is the input, is the final output $f\left( g\left( x\right) \right)$ or $g\left(f\left(x\right)\right)$?
What happens when we reverse the order?

a) When $-1$ is the input, what is the final output?

b) When $x$ is the input, what is the final output?

c) When $x$ is the input, is the final output $f\left( g\left( x\right) \right)$ or $g\left(f\left(x\right)\right)$?

If $f(x)=x-1$ and $g(x)=x^2-3x+4$ find:

a) $f\left(g\left(5\right)\right)=$
*This is read "f of g of 5"

b) $\left(f\circ g\right)\left(5\right)=$
*This is also read "f of g of 5"

c) $g\left(f\left(0\right)\right)=$

d) $\left(g\circ f\right)\left(0\right)=$

e) $f\left(f\left(1\right)\right)=$

f) $g\left(g\left(1\right)\right)=$

g) $f\left(g\left(x\right)\right)=$
*write your answer in the form $\square x^2\pm \square x\pm \square$

h) Since $f\left(g\left(x\right)\right)=x^2-3x+3$, we can now substitute directly. $f\left(g\left(5\right)\right)=$

i) $g\left(f\left(x\right)\right)=$
*write your answer in the form $\square x^2\pm \square x\pm \square$

j) Since $g\left(f\left(x\right)\right)=x^2-5x+8$, we can now substitute directly. $g\left(f\left(0\right)\right)=$

k) Solve for $x$ if $f\left(f\left(x\right)\right)=7$