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    Here is a link to the problem:
    http://postimg.org/image/lj5hd20kj/
    I don't know what dy is!
    I honestly am so tired and frustrated, I taught myself differentiation in a couple days, but integration has me pulling my hair out.
    surely the dy of y^1/2 is
    2/3 y ^3/2
    because when you differentiate you - 1 from the power, so working in reverse order.
    y^1/2+1 = y^3/2
    so what times' by 3/2 to make 1? 2/3, surely?
    but I keep getting wrong answer?
    I'm getting incredibly frustrated. have posted on here 3 times now with no help.
    Anyone?
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    (Original post by Danny.L)
    Here is a link to the problem:
    http://postimg.org/image/lj5hd20kj/
    I don't know what dy is!
    I honestly am so tired and frustrated, I taught myself differentiation in a couple days, but integration has me pulling my hair out.
    surely the dy of y^1/2 is
    2/3 y ^3/2
    because when you differentiate you - 1 from the power, so working in reverse order.
    y^1/2+1 = y^3/2
    so what times' by 3/2 to make 1? 2/3, surely?
    but I keep getting wrong answer?
    I'm getting incredibly frustrated. have posted on here 3 times now with no help.
    Anyone?
    what board are you doing?
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    (Original post by Danny.L)
    Here is a link to the problem:
    http://postimg.org/image/lj5hd20kj/
    I don't know what dy is!
    I honestly am so tired and frustrated, I taught myself differentiation in a couple days, but integration has me pulling my hair out.
    surely the dy of y^1/2 is
    2/3 y ^3/2
    because when you differentiate you - 1 from the power, so working in reverse order.
    y^1/2+1 = y^3/2
    so what times' by 3/2 to make 1? 2/3, surely?
    but I keep getting wrong answer?
    I'm getting incredibly frustrated. have posted on here 3 times now with no help.
    Anyone?

    yes ∫y^(1/2) dy = (2/3)y^(3/2) +c

    integration is the opposite of differentiation so just add one to the power then divide by it. But don't forget the constant +c because if you differentiated 3x+2 for example you would get 3... the 2 'disappears' so doing the reverse you write +c on the end to represent the unknown number.
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    (Original post by Danny.L)
    Here is a link to the problem:
    http://postimg.org/image/lj5hd20kj/
    I don't know what dy is!
    I honestly am so tired and frustrated, I taught myself differentiation in a couple days, but integration has me pulling my hair out.
    surely the dy of y^1/2 is
    2/3 y ^3/2
    because when you differentiate you - 1 from the power, so working in reverse order.
    y^1/2+1 = y^3/2
    so what times' by 3/2 to make 1? 2/3, surely?
    but I keep getting wrong answer?
    I'm getting incredibly frustrated. have posted on here 3 times now with no help.
    Anyone?
    What answer do you get for the area in the first question?
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    (Original post by davros)
    What answer do you get for the area in the first question?
    the answer is 36 but I have no idea how to get it!
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    (Original post by Danny.L)
    the answer is 36 but I have no idea how to get it!
    I must be going a bit mad then, because I get 16/3 for area A and hence 32/3 for the total area.
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    (Original post by davros)
    I must be going a bit mad then, because I get 16/3 for area A and hence 32/3 for the total area.
    (Original post by Danny.L)
    the answer is 36 but I have no idea how to get it!
    It looks like the answer box is for a mixed fraction, but davros is definitely right.
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    (Original post by buxtonarmy)
    Area A is 8/3 and hence 16/3 for the total area?
    No

    I think you might have found the area under the curve
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    (Original post by buxtonarmy)
    Area A is 8/3 and hence 16/3 for the total area?
    A = \dfrac{2}{3} \times 4^{3/2} = \dfrac{2}{3} \times 8 = \dfrac{16}{3}
 
 
 
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