Calculating a limit with tangent as denominator

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Homework Statement


lim x^3-2x^2+x/tanx
x->0


The Attempt at a Solution



All i know is that tan is going to break up into sinx/cosx so the equation will look like this

lim x^3-2x^2+x/(sinx/cosx)
x->0

I haven't worked with cubic or quadratic functions yet so I don't know where to begin with this.
 
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Tebow15 said:

Homework Statement


lim x^3-2x^2+x/tanx
x->0

Remember to throw in brackets where necessary, because the way it looks right now is

[tex]\lim_{x\to 0}\left(x^3-2x^2+\frac{x}{\tan(x)}\right)[/tex]

So you need to put brackets around the cubic to avoid this confusion :wink:
Tebow15 said:

The Attempt at a Solution



All i know is that tan is going to break up into sinx/cosx so the equation will look like this

lim x^3-2x^2+x/(sinx/cosx)
x->0

I haven't worked with cubic or quadratic functions yet so I don't know where to begin with this.

If your problem is of the form [tex]\lim_{x\to a}\left(f(x)\cdot g(x)\right)[/tex] then this is equivalent to [tex]\lim_{x\to a}f(x)\cdot\lim_{x\to a} g(x)[/tex]

So try factoring out an x from the numerator, and see if you can apply this idea correctly.
 
I may have confused you with the way I wrote it, it should look like this. (I'll use brackets to make it clearer)

lim (x^3-2x^2+x)/(sinx/cosx)
x->0
 
The answer eventually = 1 but I don't know how to get there