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    when I'm doing definite integration and I am substituting in values, I have integrated and got to

    2x^(1/2) + x between 9 and 4.

    WHy do we only use the positive values of the square root? WHat happens with the negative square root?

    Thanks!
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    Not sure if you're trolling or not but..

    

x = 1 \& -1

If

x^2 - 1 = 0
    Contrary to
    

1^{.5} = 1
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    (Original post by jgt)
    when I'm doing definite integration and I am substituting in values, I have integrated and got to

    2x^(1/2) + x between 9 and 4.

    WHy do we only use the positive values of the square root? WHat happens with the negative square root?

    Thanks!
    http://www.thestudentroom.co.uk/show....php?t=3173187
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    (Original post by jgt)
    when I'm doing definite integration and I am substituting in values, I have integrated and got to

    2x^(1/2) + x between 9 and 4.

    WHy do we only use the positive values of the square root? WHat happens with the negative square root?

    Thanks!
    \sqrt{x} \geq 0.
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    (Original post by jgt)
    when I'm doing definite integration and I am substituting in values, I have integrated and got to

    2x^(1/2) + x between 9 and 4.

    WHy do we only use the positive values of the square root? WHat happens with the negative square root?

    Thanks!
    What difference does it make anyway?

    From here, simply insert 9 into the integrated function and subtract F(4) from it.
    ie. 15 - 8 = 7, which is the answer here, irrespective of positive or negative values of radicals!
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    (Original post by Bath_Student)
    What difference does it make anyway?
    Because it would be wrong.

    From here, simply insert 9 into the integrated function and subtract F(4) from it.
    ie. 15 - 8 = 7, which is the answer here, irrespective of positive or negative values of radicals!
    ...this makes zero sense in context as to the inquiry of the OP.
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    (Original post by Zacken)
    Because it would be wrong.



    ...this makes zero sense in context as to the inquiry of the OP.
    Shut the f up
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    (Original post by GeologyMaths)
    Shut the f up
    That's the spirit!

    I can tell a fellow chemical engineer when I see one
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    (Original post by Bath_Student)
    That's the spirit!

    I can tell a fellow chemical engineer when I see one
 
 
 
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