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Math Help - Trig Identity Help

  1. #1
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    Exclamation Trig Identity Help

    I am in gr.11 just starting trig identities. I have finished all of my hw except for one question. Which looks to me like it should be simple. I just can't seem to do it. haha i'm probably just being blonde but i'll keep trying! Thanks!

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  2. #2
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    Quote Originally Posted by DaCoo911 View Post
    I am in gr.11 just starting trig identities. I have finished all of my hw except for one question. Which looks to me like it should be simple. I just can't seem to do it. haha i'm probably just being blonde but i'll keep trying! Thanks!



     \text{LHS }=  \csc^2(x) + \sec^2(x) = \frac{1}{\sin^2(x)} + \frac{1}{\cos^2(x)}

      = \frac{\cos^2(x)}{\sin^2(x)\cos^2(x)} + \frac{\sin^2(x)}{\sin^2(x)\cos^2(x)}

      = \frac{\cos^2(x) + \sin^2(x)}{\sin^2(x)\cos^2(x)}

      = \frac{1}{\sin^2(x)\cos^2(x)}

      = \csc^2(x)\sec^2(x)  = \text{RHS}
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  3. #3
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    Quote Originally Posted by DaCoo911 View Post
    I am in gr.11 just starting trig identities. I have finished all of my hw except for one question. Which looks to me like it should be simple. I just can't seem to do it. haha i'm probably just being blonde but i'll keep trying! Thanks!

    \csc^2{x} + \sec^2{x} = \frac{1}{\sin^2{x}} + \frac{1}{\cos^2{x}}

     = \frac{\cos^2{x}}{\sin^2{x}\cos^2{x}} + \frac{\sin^2{x}}{\sin^2{x}\cos^2{x}}

     = \frac{\cos^2{x} + \sin^2{x}}{\sin^2{x}\cos^2{x}}

     = \frac{1}{\sin^2{x}\cos^2{x}}

     = \csc^2{x}\sec^2{x}.
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  4. #4
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    Quote Originally Posted by Prove It View Post
    \csc^2{x} + \sec^2{x} = \frac{1}{\sin^2{x}} + \frac{1}{\cos^2{x}}

     = \frac{\cos^2{x}}{\sin^2{x}\cos^2{x}} + \frac{\sin^2{x}}{\sin^2{x}\cos^2{x}}

     = \frac{\cos^2{x} + \sin^2{x}}{\sin^2{x}\cos^2{x}}

     = \frac{1}{\sin^2{x}\cos^2{x}}

     = \csc^2{x}\sec^2{x}.
    Did you just c&p my post :P?

    Identical!

    Your coding and lack of parenthesis saves you from fraud! :P.
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