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    Hey guys I need some help with this Trigonometry General Solution.

    5cos^2(x) + 4sin(x)cos(x) - 2sin^2(x) = 2

    I have tried to change the Cos^2 to Sin^2 and vice versa using the Pythagorean identities but I cannot remove cos/sin out of 4sin(x)cos(x) to get them all into one term. I have been working on this for a few hours now but can't change it into one term or remove a term as a factor.

    Thanks so much!

    EDIT:
    I simplified it to a polynomial. 62sin^4(x) - 52sin^2(x) + 9 can you verify this.
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    (Original post by intex)
    Hey guys I need some help with this Trigonometry General Solution.

    5cos^2(x) + 4sin(x)cos(x) - 2sin^2(x) = 2

    I have tried to change the Cos^2 to Sin^2 and vice versa using the Pythagorean identities but I cannot remove cos/sin out of 4sin(x)cos(x) to get them all into one term. I have been working on this for a few hours now but can't change it into one term or remove a term as a factor.

    Thanks so much!

    EDIT:
    I simplified it to a polynomial. 62sin^4(x) - 52sin^2(x) + 9 can you verify this.
    Try writing everything in terms of \cos 2x and \sin 2x. Then you can use Rsin(x+a) methods to write the equation in the form:

    R \sin \left(2x+a\right) = b

    If you're still stuck, post your working.
 
 
 
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