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    For (1-cost)(dx/dt) = sintcotx
    I got the answer to be secx=A/(1-cost), whereas the book says secx=A(1-cost)?
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    (Original post by pippabethan)
    For (1-cost)(dx/dt) = sintcotx
    I got the answer to be secx=A/(1-cost), whereas the book says secx=A(1-cost)?
    I think the book is right, mind posting your working?
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    (Original post by pippabethan)
    For (1-cost)(dx/dt) = sintcotx
    I got the answer to be secx=A/(1-cost), whereas the book says secx=A(1-cost)?
    Got any workings?
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    (ignore the tick, I did that before I realised it was different)
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    (Original post by pippabethan)
    (ignore the tick, I did that before I realised it was different)
    integrated the RHS wrong, no minus sign needed
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    (Original post by pippabethan)
    (ignore the tick, I did that before I realised it was different)
    As above, remember that \frac{d}{dt}(1-\cos t) = -\frac{d}{dt}(\cos t) = -(-\sin t) = \sin t. So no need for the minus.
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    (Original post by Zacken)
    As above, remember that \frac{d}{dt}(1-\cos t) = -\frac{d}{dt}(\cos t) = -(-\sin t) = \sin t. So no need for the minus.
    Ooops, I completely missed that thank you!
 
 
 
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