how to you find the range of f(x)=x-4/x^2-4 PLEASE HELP
\[\frac{x-4}{x^2-4}\]?
calculus problem or something else?
guess i'll never know...
sorry! its pre cal and yest thats correct!
ok without calc it is not going to be that easy
do you have any insight on how to solve i t?
yes, and it is a pain
we are going to have to solve for x
\[y=\frac{x-4}{x^2-4}\] \[yx^2-4y=x-4\] \[yx^2-x-4y-4=0\] now we have a quadratic equation in x, so we can solve using the quadratic formula
\[x=\frac{1\pm \sqrt{1+16y^2+16y}}{2y}\]
@Mertsj if you have a snap way to do it let me know
ok we are doing the same thing
Graph it.
denominator is y^2 but it makes no difference now you have to solve \[16x^2+16x+1\geq 0\] lord!
oh no you are right, denominator is 2y
How so? a = y doesn't it?
so we have to solve [16x^2+16y+1=0\] using the quadratic formula, another pain oh yes you are right, i am wrong about the denominator
\[16x^2+16y+1=0\]
\[x=\frac{-2\pm\sqrt{3}}{4}\]
I got 8 on the bottom
also wrong, sorry range is \[(-\infty,\frac{-2-\sqrt{3}}{4}]\cup (\frac{-2+\sqrt{3}}{4},\infty)\]
well i have to admit i cheated for the last part http://www.wolframalpha.com/input/?i=16x^2%2B16x%2B1%3E0
I know. I found it.
Do you really think a pre-calc student was supposed to do that?
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