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    How do i integrate:

    2sin3xsin2x

    solomon paper A, i dont understand how they get to here??

    2sin3xsin2x = cosx - cos5x

    thanks
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    (Original post by amzy2)
    How do i integrate:

    2sin3xsin2x

    solomon paper A, i dont understand how they get to here??

    2sin3xsin2x = cosx - cos5x

    thanks
    need to use the factor formulae for trignometry
    factor formulae
    cos(A-B)-cos(A+B)=2sinAsinB
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    What is the expansion of cos (3x - 2x ) and the expansion of cos (3x + 2x)
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    cos(3x+2x) = cos3xcos2x - sin3xsin2x
    cos(3x-2x) = cos3xcos2x + sin3xsin2x
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    (Original post by rbnphlp)
    need to use the factor formulae for trignometry
    factor formulae
    cos(A-B)-cos(A+B)=2sinAsinB
    thanks - are we meant to know a few patterns like these? i was just know the double angle ones from c3 trig... :/
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    (Original post by amzy2)
    thanks - are we meant to know a few patterns like these? i was just know the double angle ones from c3 trig... :/
    I think its already given in the formulae booklet page 8
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    im dreading this exam
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    (Original post by rbnphlp)
    I think its already given in the formulae booklet page 8
    I don't think I've ever used those lower 4 formulas in a question before
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    (Original post by HitTheSwitch)
    I don't think I've ever used those lower 4 formulas in a question before
    With the A* system introduced , trust me they will come in handy
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    (Original post by rbnphlp)
    With the A* system introduced , trust me they will come in handy
    Oh great! :sigh:

    Cheers, I'll keep an eye out for those types then...
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    (Original post by rbnphlp)
    I think its already given in the formulae booklet page 8
    o right - yea i dont think i have ever used them either - this was from a solomon...tomorrow ......:eek3: :eek3: :eek3:
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    (Original post by rbnphlp)
    With the A* system introduced , trust me they will come in handy
    how come i didnt know. A* in EDEXCEL? is it unit wise or subject wise? what about other subjects?
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    (Original post by obviouslystudying)
    how come i didnt know. A* in EDEXCEL? is it unit wise or subject wise? what about other subjects?
    For all (nearly) subjects and all boards, to get an A* you have to get an average of 90% on the A2 modules as well as an average of 80% over all the modules.

    For Maths it is just C3 and C4 where you have to get an average of 90%. For Further Maths you have to get an average of 90% on your best three A2 modules as well as an average of 80% overall.
 
 
 
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