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    This question is also from the P3 June 2003 paper, question 5

    there's a curve of y = x(sin x)^1/2

    graph has a maximum point at A..


    a) Show that x-coordinate of point A satisfies equation 2tanx + x =0
    - thats alright but question b

    b)
    The finit region enclosed by the curve and the x axis is shaded in fig 1 (simply the area below the curve)
    A solid body S is generated by rotating this region around 2(pi) radians about x-axis.. Find the exact value of the volume S

    My answer is (Pi)^2 - 4.. (or 5.87 to 3 SF)..

    Can please anyone check if that's correct?
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    (Original post by hitmannq8)
    This question is also from the P3 June 2003 paper, question 5

    there's a curve of y = x(sin x)^1/2

    graph has a maximum point at A..


    a) Show that x-coordinate of point A satisfies equation 2tanx + x =0
    - thats alright but question b

    b)
    The finit region enclosed by the curve and the x axis is shaded in fig 1 (simply the area below the curve)
    A solid body S is generated by rotating this region around 2(pi) radians about x-axis.. Find the exact value of the volume S

    My answer is (Pi)^2 - 4.. (or 5.87 to 3 SF)..

    Can please anyone check if that's correct?
    you did the integration by parts right, but remember to multiply by 'pi' when working out volumes, i.e. V = pi [INT y^2 dx]
    so the answer is pi ( pi^2 - 4)
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    (Original post by hitmannq8)
    This question is also from the P3 June 2003 paper, question 5

    there's a curve of y = x(sin x)^1/2

    graph has a maximum point at A..


    a) Show that x-coordinate of point A satisfies equation 2tanx + x =0
    - thats alright but question b

    b)
    The finit region enclosed by the curve and the x axis is shaded in fig 1 (simply the area below the curve)
    A solid body S is generated by rotating this region around 2(pi) radians about x-axis.. Find the exact value of the volume S

    My answer is (Pi)^2 - 4.. (or 5.87 to 3 SF)..

    Can please anyone check if that's correct?

    use product rule and chain rule to get.
    dy/dx = (sinx)^1/2 + 1/2x(sinx)^-1/2.cosx

    um not sure to go on from there.
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    Thanx mockel!

    oww I hope i dont do a lazy mistake like forgetting that Pi .. does anyone know where can i get Edexcel past paper mark schemes online?
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    (Original post by hitmannq8)
    Thanx mockel!

    oww I hope i dont do a lazy mistake like forgetting that Pi .. does anyone know where can i get Edexcel past paper mark schemes online?
    Found one online:
    http://www.risctex.freeuk.com/
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    (Original post by meepmeep)
    Found one online:
    http://www.risctex.freeuk.com/
    trry www.ajimal.com for unofficial mark schemes
 
 
 
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