SOLUTION: {{{f(x)= (3x^2-6)/(x^2-4x)}}} {{{h(x)= 6x+2}}} find the domain of f(h(x)) I have no clue thanks bunches for help

Algebra.Com
Question 547282:

find the domain of f(h(x))
I have no clue thanks bunches for help

Answer by mathie123(224)   (Show Source): You can put this solution on YOUR website!
To find f(h(x)), we need to plug in h(x) for any x we see in f(x). This leaves:

We could expand this... though it is not needed and will take some time. Instead, we know that there is no limitations on x in the numerator. But we do know that when there is a fraction, the denominator cannot be equal to 0.
This means that
cannot equal 0.
Well... when does this expression equal 0. In other words, lets solve:

Again, we can expand this, or we could see that each term has a common factor of (6x+2) and factor this out. This leaves:


If two things multiply to give a product of 0, then at least one of them must be 0. This means



or



This means x can be anything except and .
Hopefully this helps! Please let me know if you still do not understand:)

RELATED QUESTIONS

Please help i have no clue how to do either of these problems. Given f(x)=x^2+3x-2,... (answered by fractalier)
Please help i have no clue how to do either of these problems. Given f(x)=x^2+3x-2,... (answered by fractalier)
I dont know what section I need, but can someone help me with the following problem? I... (answered by stanbon)
My problem is: Find the domain. f(x) = x³ - 2 I have no clue as to how to solve this with (answered by Edwin McCravy)
h(x) = x+6 and f(x)=x^2+4x+4 x are real numbers find the numbers not in the domain of... (answered by stanbon)
If {{{ f(x)=3x^2-4x-5 }}}, find {{{ (f(x+h)-f(x))/h... (answered by jim_thompson5910)
Please help!!! Find the difference quotient f(x+h)-f(x)over h for 2-x^2... (answered by stanbon)
Show that the derivative of f(x) = 3x^2 - 5x + 6 is 6x-5... (answered by Alan3354,Boreal)
I have to find the domain for the function. I have no clue on how to do this so any help... (answered by oscargut)