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Trigonometric identities

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    Please help! I always seem to get sinx + cosx instead of (sinx + cos)/sin2x
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    What have you done so far?
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    (Original post by metrize)
    What have you done so far?
    it's reallyyy lengthy, but i can get it simplified down to this
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    (Original post by Stanspam)
    it's reallyyy lengthy...
    Just take a picture, otherwise we can't tell you where you went wrong
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    this
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    oh, it's supposed to be 4 on the denominator instead of 2
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    (Original post by Stanspam)
    oh, it's supposed to be 4 on the denominator instead of 2
    Well just use double angle on it.

    Do you know how to add fractions? \displaystyle \frac{a}{b}+\frac{c}{d}=\frac{ad  +bc}{bd} ??? Use it.

    The denominator would go to 1-\cos^2(2x) which is equivalent to \sin^2(2x)
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    (Original post by Stanspam)
    this
    This can still be simplified to the expression the question asks for.
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    (Original post by B_9710)
    This can still be simplified to the expression the question asks for.
    nope. sorry, still not getting it
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    (Original post by Stanspam)
    nope. sorry, still not getting it
    2\sin(x)\cos(x) \equiv \sin(2x)
 
 
 
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