Hello all, again.(adsbygoogle = window.adsbygoogle || []).push({});

Simple question.

Compute [tex]\int_{9}^{4} (x - \frac{1}{\sqrt{x}}) dx[/tex]

I did this:

[tex]\int_{9}^{4} (x - \frac{1}{x^{0.5}}) dx[/tex] = [tex]\int_{9}^{4} (x - x^{-0.5}) dx[/tex]

[tex]\left[ \frac{1}{2} x^2 - 2 x^{0.5} \right]_{9}^{4}[/tex] = [tex]\left[ \frac{x^2}{2} - 2 \sqrt{x} \right]_{9}^{4}[/tex]

[tex](\frac{81}{2} - 6) - (\frac{16}{2} - 4) = \frac{81 - 12}{2} - \frac{16 - 8}{2} = \frac{69}{2} - \frac{8}{2} = \frac{61}{2} = 30.5[/tex]

2 months of calculus and and still I am not sure of what I have done wrong. The answers in my book gives [tex]10 \frac{2}{3}[/tex]

So if it is right then can someone enlighten me to what I have done wrong please.

Cheers

The Bob (2004 ©)

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# Homework Help: Simply Checking an Answer in Calculus

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