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Thread: finding limit of trig

  1. #1
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    finding limit of trig

    any idea on how to solve this i have no idea where to start on these type of functions ?

    limit of (4x/tanx)
    x> (pie/4)

    x is approaching pie over 4
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  2. #2
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    What do you think of this?

    $\displaystyle \lim_{x\to \frac{\pi}{4}}\frac{4x}{\tan x}$

    $\displaystyle = \frac{4\frac{\pi}{4}}{\tan \frac{\pi}{4}}$

    $\displaystyle
    = \frac{\pi}{1} = \pi
    $
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  3. #3
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    Quote Originally Posted by maybnxtseasn View Post
    any idea on how to solve this i have no idea where to start on these type of functions ?

    limit of (4x/tanx)
    x> (pie/4)

    x is approaching pie over 4
    It's in determinant form isn't it? You don't need to do any simplification. You can use direct substitution.

    $\displaystyle \tan\left(\frac{\pi}{4}\right)=1$

    $\displaystyle 4\left(\frac{\pi}{4}\right)=\pi$

    So $\displaystyle \lim_{x->\frac{\pi}{4}}\frac{4x}{\tan(x)}=\pi$
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