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I am helping with homework.

I am stumped here - What is the meaning of the small round circle, or small "o" in question 19 (that I underlined) and question 20

Camera shot of example

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@Ray,en.wikipedia.org/wiki/Function_composition –  pedja Oct 2 '11 at 17:31

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It is function composition. If you have one function $f(x)$, and another function $g(x)$, then we can create a new function named $g\circ f$ (read as: "$g$ composed with $f$") that is defined as $$(g\circ f)(x)=g(f(x))$$ For example, if $f(x)=x+1$, and $g(x)=2x-1$, then $$(g\circ f)(x)=g(f(x))=g(x+1)=2(x+1)-1=2x+1$$

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Use of this symbol makes it possible to efficiently write things like $(g\circ f)^{-1} = f^{-1}\circ g^{-1}$. –  Michael Hardy Oct 2 '11 at 17:31
    
So does question 19 solve out to 16x^2 - 1 –  Raj More Oct 2 '11 at 17:37
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@RajMore It goes like $h(4x+1) = (4x+1)^2-2 = 16x^2+8x+1-2 = 16x^2+8x-1$. –  user13838 Oct 2 '11 at 17:41
    
Doh me! It's slooooooooowly coming back to me –  Raj More Oct 2 '11 at 17:43

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