Recent content by bubblygum

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    How can I expand sin(x + y) + sin(x - y) to get 2sinxcosy?

    Great, solved it thanks. Is the second one even possible?
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    How can I expand sin(x + y) + sin(x - y) to get 2sinxcosy?

    Proving trig identities I have 2 more this time, thanks for the time! Homework Statement -sin^2x-sin^2y+1=cos(x+y)cos(x-y) Homework Equations Compound, double, pythagorean, reciprocal, quaotient, etc. The Attempt at a Solution R.H.S. cos(x+y)cos(x-y) =...
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    Proving Trig Identity: Tanx = Csc2x - Cot2x | Homework Help

    I'm still stuck with : tanx = csc2x - cot2x RS 1/sin2x - cos2x/sin2x 1/2sinxcosx - cos^2x-sin^2x/2sinxcosx 1-cos^2x-sin^2x/2sinxcosx 1-(cosx+sinx)(cosx-sinx)/sinxcosx+sinxcosx
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    Proving Trig Identity: Tanx = Csc2x - Cot2x | Homework Help

    Thank you! Yes, I have learned the double angle ones, i'll give it a shot now.
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    Proving Trig Identity: Tanx = Csc2x - Cot2x | Homework Help

    Homework Statement tanx=csc2x-cot2x Homework Equations Quotient, Reciprocal, Pythagoreans The Attempt at a Solution 1/sinx + 1/sinx - cosx/sinx - cosx/sinx = 2/sinx - 2cosx/sinx = (2-2cosx)/sinx STUCK~