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    Hi, just trying to check my answer, whats the integral between x=2, x=0 of:

    -1 + (1/2)/(1+X) + (5/2)/(3-x)

    Find the answer in the form p+qlnr

    Ive done it but need to check my answer, Thanks.
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    (Original post by ResidentEvil)
    Hi, just trying to check my answer, whats the integral between x=2, x=0 of:

    -1 + (1/2)/(1+X) + (5/2)/(3-x)

    Find the answer in the form p+qlnr

    Ive done it but need to check my answer, Thanks.
    Well -i got:

    -x + 0.5ln((1+x)/(3-x)^5)
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    Is that what you have got - cos i am doubting what i have done
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    (Original post by ResidentEvil)
    Hi, just trying to check my answer, whats the integral between x=2, x=0 of:

    -1 + (1/2)/(1+X) + (5/2)/(3-x)

    Find the answer in the form p+qlnr

    Ive done it but need to check my answer, Thanks.
    -x+0.5ln|2+2x|-2.5ln|6-2x| is what I get for the integration.
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    So i got:

    -2 + 0.5 ln 729
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    (Original post by Silly Sally)
    So i got:
    -2 + 0.5 ln 729
    I also get that answer. Since 729 = 3^6, it simplifies to -2 + 3 ln(3).
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    i got -1+3ln3
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    (Original post by lexazver203)
    i got -1+3ln3
    (int from 0 to 2) -1 + (1/2)/(1 + x) + (5/2)/(3 - x) dx
    = [ -x + (1/2) ln(1 + x) - (5/2) ln(3 - x) ] (from 0 to 2)
    = -2 + (1/2) ln(3) + (5/2) ln(3)
    = -2 + 3 ln(3).
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    omg u all got diffferent answers :confused: !

    (Original post by Jonny W)
    (int from 0 to 2) -1 + (1/2)/(1 + x) + (5/2)/(3 - x) dx
    = [ -x + (1/2) ln(1 + x) - (5/2) ln(3 - x) ] (from 0 to 2)
    = -2 + (1/2) ln(3) + (5/2) ln(3)
    = -2 + 3 ln(3).
    Johnny tell me HOW exactly is
    integral of +(5/2)/(3-x)
    = -(5/2)ln(3-x)?
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    (Original post by ResidentEvil)
    omg u all got diffferent answers :confused: !



    Johnny tell me HOW exactly is
    integral of +(5/2)/(3-x)
    = -(5/2)ln(3-x)?
    to do it in a lengthly method:

    use u=(3-x) => du = -dx

    (5/2)/(3-x) = (5/2)/u

    => integral (5/2)/(3-x) = integral (5/2)/u -du = -5/2 integral 1/u du
    = -5/2 ln(u) = -5/2 ln(3-x)
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    (Original post by ResidentEvil)
    omg u all got diffferent answers :confused: !



    Johnny tell me HOW exactly is
    integral of +(5/2)/(3-x)
    = -(5/2)ln(3-x)?
    keep (5/2) out of the integral sign, sonce it is a constant, so you get:

    (5/2) [int 1/(3-x) dx]

    intgral of 1/(3-x) is -ln(3-x)

    so multiplying by the constant gives, (-5/2)ln(3-x)
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    ohh is it because of the "-x"??
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    (Original post by ResidentEvil)
    ohh is it because of the "-x"??
    yeah
 
 
 
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