Ok i know how to solve compositions when Im provided with x

Here I am dealing with f of g of h

f(x) = 2x-2

g(x) = x^2

h(x) = 9-x

so its f(g(h(x)

But how do i start without an x value?

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- Sep 13th 2011, 01:18 PMGaDoomZQuestion about Composition Functions
Ok i know how to solve compositions when Im provided with x

Here I am dealing with f of g of h

f(x) = 2x-2

g(x) = x^2

h(x) = 9-x

so its f(g(h(x)

But how do i start without an x value? - Sep 13th 2011, 01:23 PMPlatoRe: Question about Composition Functions
- Sep 13th 2011, 01:34 PMGaDoomZRe: Question about Composition Functions
Oh I see haha, guess that was a stupid mistake on my part. Guess I just had to leave X as X...

- Sep 13th 2011, 01:39 PMGaDoomZRe: Question about Composition Functions
Ok how about

f(x) = √x

g(x) = 7√1-x

I tried √7-x, √x, √7x they were all wrong - Sep 13th 2011, 01:55 PMHallsofIvyRe: Question about Composition Functions
I don't know what you meant by "tried". Plato told you how to find the compositions.

$\displaystyle f\circ g(x)= f(g(x))= f(7\sqrt{1-x}}= \sqt{7\sqrt{1-x}}$

which could also be written

$\displaystyle \sqrt{7}\sqrt[4]{1- x}$

$\displaystyle g\circ f(x)= g(f(x))= g(\sqrt{x})= 7\sqrt{1- \sqrt{x}}$ - Sep 13th 2011, 02:10 PMGaDoomZRe: Question about Composition Functions
When I submitted both of those, it was marked as wrong...

even after simplfying it down to

√7-x and 7-√x - Sep 13th 2011, 02:15 PMPlatoRe: Question about Composition Functions
- Sep 13th 2011, 02:50 PMGaDoomZRe: Question about Composition Functions
Nope, still didn't work... I am out of submissions now :(

- Sep 13th 2011, 04:17 PMGaDoomZRe: Question about Composition Functions
- Sep 13th 2011, 04:28 PMPlatoRe: Question about Composition Functions
I think that there must be a flaw in what program you are using.

If this is indeed correct $\displaystyle g(x)=7\sqrt{1-x}$

then $\displaystyle g\circ g(x)=7\sqrt{1-7\sqrt{1-x}~}$.

If the program does not take that, then either you are typing the symbols incorrectly or there is a flaw in the program. - Sep 13th 2011, 05:39 PMGaDoomZRe: Question about Composition Functions
- Sep 13th 2011, 05:56 PMPlatoRe: Question about Composition Functions
Then that is a totally incompetent program or you do not know how to use it. I suspect that you are not using enough grouping symbols.

Look at my LaTeX code:

7\sqrt{1-7\sqrt{1-x}} this gives $\displaystyle 7\sqrt{1-7\sqrt{1-x}}$.

Note how carefully the various parts are grouped together using grouping symbols.

Does that program allow LaTeX coding?

If so the you can*copy and paste*from here.

In any case,**you need to contact the program administrator**to discuss these concerns. - Sep 13th 2011, 06:30 PMGaDoomZRe: Question about Composition Functions
You are correct plato, I was not inputting the second 7 properly. Thank you again