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    Dear TSR, I am lost as to the second step of the following question:


    Given that y= 3x^1/2 - 4x^-1/2 (x>0)
    (a) Find dy/dx
    (b) Find ∫ydx.

    I presumed that the second step was meant to prove the first step and simply integrated the answer from (a), but then checked the answer and was wrong. I have no clue what (b) actually wants me to do/find, as I haven't encountered ∫ydx as opposed to ∫(x^n)dx before.

    If you could just tell me what to do to find ∫ydx that would be just as good if not better than actually going through this specific example... thanks.
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    (Original post by Philosopher-of-sorts)
    Dear TSR, I am lost as to the second step of the following question:


    Given that y= 3x^1/2 - 4x^-1/2 (x>0)
    (a) Find dy/dx
    (b) Find ∫ydx

    I presumed that the second step was meant to prove the first step and simply integrated the answer from (a), but then checked the answer and was wrong. I have no clue what (b) actually wants me to do/find, as I haven't encountered ∫ydx as opposed to ∫(x^n)dx before.

    If you could just tell me what to do to find ∫ydx that would be just as good if not better than actually going through this specific example... thanks.
    Integrate y. . .
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    (Original post by Philosopher-of-sorts)
    Dear TSR, I am lost as to the second step of the following question:


    Given that y= 3x^1/2 - 4x^-1/2 (x>0)
    (a) Find dy/dx
    (b) Find ∫ydx.

    I presumed that the second step was meant to prove the first step and simply integrated the answer from (a), but then checked the answer and was wrong. I have no clue what (b) actually wants me to do/find, as I haven't encountered ∫ydx as opposed to ∫(x^n)dx before.

    If you could just tell me what to do to find ∫ydx that would be just as good if not better than actually going through this specific example... thanks.
    Well, you know that y=3x^1/2 - 4x^-1/2, and you are asked to integrate y. So substitute:

    ∫ydx = ∫(3x^1/2 - 4x^-1/2)dx

    ...and there you have your ∫(x^n)dx form.
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    Just integrate y and you're done!
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    Bahaha that I just spent 20 minutes trying to integrate dy/dx to something strange and wondering what I was doing wrong because I can't read properly.

    Thanks for your help.
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    (Original post by Philosopher-of-sorts)
    Bahaha that I just spent 20 minutes trying to integrate dy/dx to something strange and wondering what I was doing wrong because I can't read properly.

    Thanks for your help.
    Happens to us all!
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    (Original post by Beth1234)
    Happens to us all!
    This!
 
 
 
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