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Math Help - Help with Trigonometric Identities

  1. #1
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    Help with Trigonometric Identities

    sec^2{x}+tan^2{x}sec^2{x}=sec^4{x}

    So far I have changed everything to fractions using the quotient properties, but I have no idea where to go next.
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  2. #2
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    Use the identity \displaystyle \tan^2{x} + 1 = \sec^2{x} \implies \tan^2{x} = \sec^2{x} - 1.

    Substitute this into the LHS and simplify.
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  3. #3
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    Sorry, but what does LHS stand for?
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  4. #4
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    Quote Originally Posted by toeknee View Post
    Sorry, but what does LHS stand for?
    Left Hand Side. Meaing if we have the expression a + 1 = b then the LHS is a + 1.

    -Dan
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  5. #5
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    Left Hand Side
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  6. #6
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    You can still use the Pythagorean property for tan^2{x}sec^2{x}?
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  7. #7
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    Surely \displaystyle \tan^2{x}\sec^2{x} = (\sec^2{x} - 1)\sec^2{x}...
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  8. #8
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    I thought because it was one term, you couldn't, but I guess not. Thanks a lot for your help. Kind of fitting that your name is Prove It.
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