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    I don't know how to do this.

    I get that answers but there's a minus in front! I thought when u integrate sin u get -cos

    could someone please go through the steps? thankyou.
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    let u = sin t => du = cos t dt

    then ∫u5 du
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    (Original post by FoOtYdUdE)


    I don't know how to do this.

    I get that answers but there's a minus in front! I thought when u integrate sin u get -cos

    could someone please go through the steps? thankyou.
    Yes, this is correct.

    Do you use the "trig wheel"? I always use it, as silly as it looks...and it works great!

    ___S

    -C____C

    ___-S

    It's like a wheel, see? (sorry my 'art' is so awful - but bear with me!)

    S means sin, C means cos. Start from, say, S...if you differentate you go down (clockwise), to get cos. Differentiate cos and you get -sin...etc.

    If instead you wanted to integrate and start with, say, -cos...you integrate and you get -sin (going anti-clockwise now), integrate again and get cos...


    I'm a 2nd year physics student (at university) and I still use this method to do calculus with trig functions. I just scribble it in the margin and I never get confused. Try it out!


    EierVonSatan's method was, predictably, completely correct, by the way .
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    (Original post by M_E_X)
    Yes, this is correct.

    Do you use the "trig wheel"? I always use it, as silly as it looks...and it works great!

    ___S

    -C____C

    ___-S

    It's like a wheel, see? (sorry my 'art' is so awful - but bear with me!)

    S means sin, C means cos. Start from, say, S...if you differentate you go down (clockwise), to get cos. Differentiate cos and you get -sin...etc.

    If instead you wanted to integrate and start with, say, -cos...you integrate and you get -sin (going anti-clockwise now), integrate again and get cos...


    I'm a 2nd year physics student (at university) and I still use this method to do calculus with trig functions. I just scribble it in the margin and I never get confused. Try it out!


    EierVonSatan's method was, predictably, completely correct, by the way .
    Awww, beautifully explained.
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    (Original post by EierVonSatan)
    let u = sin t => du = cos t dt

    then ∫u5 du
    Brilliant!
 
 
 
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