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Math Help - trigonometry

  1. #1
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    trigonometry

    how do i show that tangent squared 8x all divided by sin4x multiply by sin2x is equal to 8 and x gets closer to 0
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  2. #2
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    Quote Originally Posted by Rose Wanjohi View Post
    how do i show that tangent squared 8x all divided by sin4x multiply by sin2x is equal to 8 and x gets closer to 0
    huh? you are talking about limits here, right?

    do you mean: \lim_{x \to 0} \frac {\tan^2 8x}{\sin 4x \cdot \sin 2x} or \lim_{x \to 0} \frac {\tan^2 8x}{\sin 4x} \cdot \sin 2x ?

    it seems you mean the first.

    Hint: multiply by \frac {64x^2 \cdot 4x \cdot 2x}{64x^2 \cdot 4x \cdot 2x}, rearrange and apply the limits according to the special limits you've learned \left( \lim_{x \to 0} \frac {\sin x}x = 1 \text{ and } \lim_{x \to 0} \frac {\tan x}x = 1 \right)
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  3. #3
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    yeah

    i meant limits and you almost answered my question but when i tried doing it, i get an answer, 1/8 instead of 8 what am i doing wrong?
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  4. #4
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    Quote Originally Posted by Rose Wanjohi View Post
    i meant limits and you almost answered my question but when i tried doing it, i get an answer, 1/8 instead of 8 what am i doing wrong?
    If you expect an answer to this question you will need to show your working.
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