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C3 Addition Formulae Help Watch

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    Please can somebody solve this for me please?

    2Sin(x)=Cos(x-45)

    Thanks
    • Community Assistant
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    Use the addition formulae on cos(x-45)
    evaluate cos45 and sin45 and rearrange.
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    expand the RHS. put in the value of cos 45° and sin 45°.

    rearrange to get all the sinx on the left & the cosx on the right....*
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    (Original post by NotNotBatman)
    Use the addition formulae on cos(x-45)
    evaluate cos45 and sin45 and rearrange.
    I've tried that method but I keep getting the same answer which isn't correct. I get x= 61.325, is this what you get?
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    (Original post by gtmharnett)
    I've tried that method but I keep getting the same answer which isn't correct. I get x= 61.325, is this what you get?
    I got 28.7. Post your full working and we'll find where you're going wrong.
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    (Original post by gtmharnett)
    I've tried that method but I keep getting the same answer which isn't correct. I get x= 61.325, is this what you get?
    No, show some more working.
 
 
 
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