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    1st question is: sin( theta+pi/6)=3cos(theta-pi/6) in the range -180 to 180.
    2nd question is : cos(x+pi/6)+sin(x+pi/3)= root3cosx

    I have tried messing around with identities to see if it works but have failed so far , i tried using double angle identities but the way i rearranged didn't meet the requirements so they didn't work either. Don't know what to do.
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    (Original post by Nirm)
    1st question is: sin( theta+pi/6)=3cos(theta-pi/6) in the range -180 to 180.
    2nd question is : cos(x+pi/6)+sin(x+pi/3)= root3cosx

    I have tried messing around with identities to see if it works but have failed so far , i tried using double angle identities but the way i rearranged didn't meet the requirements so they didn't work either. Don't know what to do.
    compound identities first
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    (Original post by TeeEm)
    compound identities first
    Okay i did that for question 1 but cant figure anything out from then onwards :confused:
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    (Original post by Nirm)
    Okay i did that for question 1 but cant figure anything out from then onwards :confused:
    You do know what cos and sin of pi/6 are don't you?
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    (Original post by Nirm)
    Okay i did that for question 1 but cant figure anything out from then onwards :confused:
    both work the same way

    look at some examples of similar questions in the following PDF

    PDF.pdf

    hope it is useful
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    (Original post by TenOfThem)
    You do know what cos and sin of pi/6 are don't you?
    Just face palmed my self, completely forgot about the special triangles. Now i can solve it :mwuaha:
    Thanks you!
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    (Original post by Nirm)
    Just face palmed my self, completely forgot about the special triangles. Now i can solve it :mwuaha:
    Thanks you!
 
 
 

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