F(x)= (x^2 + 2)/ (x + 4)

a) What is the domain of f?

b)List the x-intercepts, if any, of the graph of f.

c)List the y-intercept, if there is one, of the graph of f.

Thank you!

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- Jul 13th 2008, 05:26 PMspinkaFunctions of their graphs
**F(x)= (x^2 + 2)/ (x + 4)**

a) What is the domain of f?

b)List the x-intercepts, if any, of the graph of f.

c)List the y-intercept, if there is one, of the graph of f.

Thank you! - Jul 13th 2008, 05:35 PMo_O
(a) What x values can the function

**not**have? Hint: Denominator = 0?

(b)To find the x-intercept, notice that the y-coordinate will be equal to 0. So set f(x) = 0 and solve for x, i.e.:

$\displaystyle 0 = \frac{x^{2} + 2}{x+4}$ (Can you even solve this? If not, what does that mean?)

(c) To find the y-intercept, notice that the x-coordinate will be equal to 0. So replace each x with a 0 and solve for f(0). - Jul 13th 2008, 05:55 PMspinka
a) -4

b) x-intercept = 0

c) y-intercept = 1/2

Are these values correct? - Jul 13th 2008, 06:00 PMo_O
Just to reiterate, what you got for (a) is the value you

**cannot**have in your domain.

All is correct except for (b).

Remember that whatever you x-intercept is, it will have a**y-coordinate**of 0. If you plug in x = 0 into f(x), do you get 0? - Jul 13th 2008, 06:07 PMspinka
B) would the answer be undefined?

Thanks. - Jul 13th 2008, 06:09 PMo_O
Not undefined. Just that it doesn't exist! Since you can't find a solution, it means your graph doesn't have a x-intercept.