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    http://mathsathawthorn.pbworks.com/f/FP3+2008.pdf
    In 6bii? Okay so ive shown the equation they have gave ,what do i do next?
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    Integrate it. Put the cos(theta) into the dx and integrate with respect to sin(x) giving you sin(x) to the power of 5 divided by 5. Put in limits and multiply by 6pi
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    (Original post by 130398)
    Integrate it. Put the cos(theta) into the dx and integrate with respect to sin(x) giving you sin(x) to the power of 5 divided by 5. Put in limits and multiply by 6pi
    https://www.youtube.com/watch?v=_prw...7dwdx20UbChE24
    Okay so at 14.18 they have put as u=sintheta? How am i supposed to know that?
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    (Original post by Ayaz789)
    https://www.youtube.com/watch?v=_prw...7dwdx20UbChE24
    Okay so at 14.18 they have put as u=sintheta? How am i supposed to know that?
    It's a common c4 integral really. Use udv dv du or whatever it was. If you're doing FP3 you may be asked to use a substitution of your choice. That was popular in older papers but the newer ones (Edexcel at least) don't do it as much.
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    Messy but oh well. That's how I would have done it.
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    (Original post by 130398)
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    Messy but oh well. That's how I would have done it.
    So you just integrated the cosx seperately? Its fine , its not messy haha
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    (Original post by Ayaz789)
    So you just integrated the cosx seperately? Its fine , its not messy haha
    Basically for this integral you are considering the derivatice of  \sin^5 x . This person basically made a substitution of  u=\sin x . For these types of integrals it's really helpful if you can learn to recognise them. As well as the intergals of  \tan^n x \sec^2 x and  \sec^n x \tan x .
 
 
 
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