## Given f, g, find 3(f+g)(2), (g*f)(-2), g(f(x)), (f*g)(x),

Quadratic equations and inequalities, variation equations, function notation, systems of equations, etc.
Kayto
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### Given f, g, find 3(f+g)(2), (g*f)(-2), g(f(x)), (f*g)(x),

1) Given f(x) = 2(squareroot of) x+1 and g(x) = (squareroot of) 2x-1 simplify 3(f+g)(2)

2) Given f(x) = 1-x^2 and g(x) = 2x + 1 evaluate (g . F) (-2)

3) Given g(x) = (squareroot of) 3 - 2x and f(x) - |x-2| A) find g(f(x)) B) State if the composite functions exists

4) Given f(x) = X /(2-x) and g (x) = 3/(x) A) Find (f . g) (x) B) State any restrictrions

5) G(x) = (-3/5)x + 2 and its inverse.

stripling_warrior
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### Re: Given f, g, find 3(f+g)(2), (g*f)(-2), g(f(x)), (f*g)(x),

Do you mean...

1. Given $f(x)=2(\sqrt{x+1})$ and $g(x)=\sqrt{2x-1}$ simplify $3(f+g)(2)$

2. Given $f(x)=1-x^2$ and $g(x)=2x+1$ evaluate $(g . f)(-2)$

3. Given $g(x) =\sqrt{3 - 2x}$ and $f(x) - |x-2| A)$ find $g[f(x) B]$ State if the composite functions exists

4. Given $f(x) = \frac{x}{2-x}$ and $g (x) = \frac{3}{ (x)a}$ Find $(f . g) (x) B)$ State any restrictrions

5. Given $(x) = (\frac{-3}{5})x + 2$ and its inverse.
Last edited by stripling_warrior on Wed May 13, 2009 9:23 pm, edited 1 time in total.

Kayto
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### Re: Given f, g, find 3(f+g)(2), (g*f)(-2), g(f(x)), (f*g)(x),

Yes sorry don't know how to do those symbols on here.

Martingale
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### Re: Given f, g, find 3(f+g)(2), (g*f)(-2), g(f(x)), (f*g)(x),

The composition of functions $(f\circ g)(x)$

can be written using

(f\circ g)(x)

stapel_eliz
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Kayto wrote:1) Given f(x) = 2(squareroot of) x+1 and g(x) = (squareroot of) 2x-1 simplify 3(f+g)(2)

To learn how to "operate" on functions, try here.

Then evaluate f(2) and g(2), add the results, and multiply by 3.

Kayto wrote:2) Given f(x) = 1-x^2 and g(x) = 2x + 1 evaluate (g . F) (-2)

Assuming "(g.F)" means $(g\,\times\,f)$, then find g(-2) and f(-2), and multiply.

Kayto wrote:3) Given g(x) = (squareroot of) 3 - 2x and f(x) - |x-2| A) find g(f(x)) B) State if the composite functions exists

To learn how to compose functions, try here.

Kayto wrote:4) Given f(x) = X /(2-x) and g (x) = 3/(x) A) Find (f . g) (x) B) State any restrictrions

Multiply the two rational expressions. Check for the x-values which would cause division by zero.

Kayto wrote:5) G(x) = (-3/5)x + 2 and its inverse.

To learn how to find inverse functions, try here.