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    How do i go along to answer this and finding C?? I end up getting the wrong answer for C! please show me how to work this out!!
    Thanks
    Question is in attachment!!

    Thanks in advance!
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    You know that xrootx is x^3/2, yes?
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    integrate normally, then sub x=4, and make y=35, solve for C
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    difficult to see the power of 5x, what is it?

    EDIT: you might as well type it out for us
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    (Original post by cpm1)
    You know that xrootx is x^3/2, yes?
    yes when i integrated i got the following properly i get the following: 10x^1/2 +2/5x^5/2 +C

    But then i know you have to find C but how do i do it? Please help!!!

    Thanks
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    (Original post by ilyking)
    difficult to see the power of 5x, what is it?

    EDIT: you might as well type it out for us
    its 5x^-1/2 + x root x

    How to find C. can u kindly show me step by step!

    Thanks
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    (Original post by mujahid_e3)
    yes when i integrated i got the following properly i get the following: 10x^1/2 +2/5x^5/2 +C

    But then i know you have to find C but how do i do it? Please help!!!

    Thanks
    You are given in the question that y=35 when x=4 and you now have the equation for y so substitute the x and y values in. C is what you need to add to the x side with 4 substituted in to get 35.

    C is the constant of integration meaning that it remains constant regardless of the values you put in. Once you have found it, you can find y for any value of x.
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    (Original post by dstevens)
    You are given in the question that y=35 when x=4 and you now have the equation for y so substitute the x and y values in. C is what you need to add to the x side with 4 substituted in to get 35.

    C is the constant of integration meaning that it remains constant regardless of the values you put in. Once you have found it, you can find y for any value of x.
    so it would be:
    35= 10 * 4^1/2 + 2/5 * 4 ^5/2 ?
    this is 35= ????
    im a bit stuck please help me complete!!
    Thanks
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    (Original post by mujahid_e3)
    so it would be:
    35= 10 * 4^1/2 + 2/5 * 4 ^5/2 ?
    this is 35= ????
    im a bit stuck please help me complete!!
    Thanks
    10*4^1/2 is the same as 10*sqrt(4) which equals 20

    4^5/2 is the same as sqrt(4^5) which is sqrt(1024) which equals 32

    So you have 35=20+32+C and you can solve for C
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    can really read the dy/dx part, i think its 5x^1/2 + xrootx

    if you integrate that you'll get 10x^1/2 + 2/5 x^5/2 + C

    we're give than when x=4 y =35

    substitue x=4 into that equation

    so 20 + 12.8 + C = 35
    therefore C = 2.2

    is that right?

    y = 10x^1/2 + 2/5 x^5/2 + 2.2
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    (Original post by sohail.s)
    can really read the dy/dx part, i think its 5x^1/2 + xrootx

    if you integrate that you'll get 10x^1/2 + 2/5 x^5/2 + C

    we're give than when x=4 y =35

    substitue x=4 into that equation

    so 20 + 12.8 + C = 35
    therefore C = 2.2

    is that right?

    y = 10x^1/2 + 2/5 x^5/2 + 2.2
    Yes your right i checked... But how did you get the C? i am a bit stuck!!! Because i wasnt sure how to work it out! can u plz show me?

    Thanks
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    (Original post by mujahid_e3)
    Yes your right i checked... But how did you get the C? i am a bit stuck!!! Because i wasnt sure how to work it out! can u plz show me?

    Thanks
    C is the constant of integration
    to find C substitute youe value of x (given) into the equation you just found by integration
    make the equation equal to the value of y (given) and solve to find C

    after integrating

    y= 10x^1/2 + 2/5 x^5/2 + C
    we are told that y=35 when x=4

    put x=4 into the equation y= (10*2) + (2/5 * 32) + C

    y=35 so 20 + 12.8 + C = 35

    therefore C = 2.2

    so y= 10x^1/2 ~ 2/5x^5/2 + 2.2
 
 
 
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