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    Hi,
    I am doing the edexcel board.
    Right I need a worked example of find x between 0 and 360 for 3sin(x+10)=3cos(x-10) (all in degree not radians.) I missed a couple of lesson and I am trying to catch up a whole sectionover the weekend so I dont get too far behind..
    Regards,
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    This page should help. Expand the trig functions appropriately then try to find a way to simplify the resulting equation.
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    Okay its the simplifying I have difficulty with.

    When expanded you get 3 (Sinxcos10+sin 10cosx)= 4(this was a typo before as 3) (cos10cosx+sinx sin10)

    Directions on how to simplify would be useful
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    Anyone^^??
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    3(sin x cos 10 + cos x sin 10)=4(cos x cos 10 + sin x sin 10)
    cos 10 = 1 (approx)
    sin 10 = 0.2 (approx)
    3sin x + 0.6cos x = 4cos x + 0.2sin x
    2.2sin x = 3.4 cos x
    tan x = 1.55
    now finding x is easy
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    kk... You see I wasnt sure when to get enumerate value of cos and sin 10 obvious;y wanting to keep my answer as accurate as possible...
    Thank you so much
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    (Original post by HarryWinston)
    kk... You see I wasnt sure when to get enumerate value of cos and sin 10 obvious;y wanting to keep my answer as accurate as possible...
    Thank you so much
    np man.....anytime
 
 
 
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Updated: November 8, 2008

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