Confused, but tried it this way:(adsbygoogle = window.adsbygoogle || []).push({});

Use u-substitution to show that (for y a positive number and x>0)

[tex]\int_{x}^{xy} \frac{1}{t} dt = \int_{1}^{y} \frac{1}{t} dt [/tex]

so, u=t and du=dt

if x=1

t=xy u=y(1)=y

t=x u=1

or

u=1/t and du/ln [t] = dt

if x=1

t=xy u=1/y

t=x y=1

Thanks for your help

Todd

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# Homework Help: Logarithm defined as integral

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