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    Solved.
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    2sinx + cosx = 0
    2sinx/cosx + cosx/cosx = o
    2tanx + 1 = 0
    tanx = -0.5
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    (Original post by WildBerry)
    I'm confused how to solve 2sinx + cos x=0 ,

    There isn't any identity I could use ?

    I thought of making it tan, but then I can't divide both sides because the cosx has a + sign infront, so I can only subtract the cosx from both sides ?
    Why not?
    If you divide +cos(x) by cos(x) you get +1.
    If you divide -cos(x) by cos(x) you get -1.
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    You can divide by cos(x) ^^
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    Thanks, got it now

    However doing another question now why does cos^2x/cosx become only cosx ? Doesn't the bottom go into the top twice, so it'd be 2cosx/1 ?
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    What happens if you have \frac{x^2}{x}?
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    (Original post by Ben121)
    What happens if you have \frac{x^2}{x}?
    Oh the indices rule ? Subtract top from bottom ?
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    (Original post by WildBerry)
    Oh the indices rule ? Subtract top from bottom ?
    Yes,

    x2 / x1

    = x2-1

    = x1

    = x
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    Thanks all
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    This thread makes my head hurt.
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    (Original post by wtfCharlie)
    This thread makes my head hurt.
    The maths here isn't that complicated, its just my incompetence at remembering /knowing the basic methods that were used in C1 / gcse .
 
 
 

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