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    How the hell do I solve this question, I'm confused +rep

    Given that Sinx=3/5, use an appropriate double angle formula to find the exact value of sec2x
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    (Original post by I Have No Imagination)
    How the hell do I solve this question, I'm confused +rep

    Given that Sinx=3/5, use an appropriate double angle formula to find the exact value of sec2x
    :confused:
    1/cos2x=sec2x

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    cos2x=1-2sin^2(x)(you know what sin x is )
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    (Original post by rbnphlp)
    1/cos2x=sec2x

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    cos2x=1-2sin^2(x)(you know what sin x is )
    What??

    So you're saying its 1-2sin^2(3/5)??
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    (Original post by I Have No Imagination)
    What??

    So you're saying its 1-2sin^2(3/5)??
    it means sin^2x =sinx.sinx
    can you square 3/5?
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    (Original post by rbnphlp)
    it means sin^2x =sinx.sinx
    can you square 3/5?
    Ah yeah I see, cheers. :yy:

    Repped.
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    (Original post by I Have No Imagination)
    Ah yeah I see, cheers. :yy:

    Repped.
    appreciated
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    (Original post by I Have No Imagination)
    What??

    So you're saying its 1-2sin^2(3/5)??
    You are going the right way.Just go ahead.....and calculate by the formula you mentioned.Then finally reciprocal.
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    oh i am late...it has been solved!
 
 
 
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