My Professor in my calculus class (1st year) left us with this question at the end of lecture today and told us to think about it. I am baffled as to how to solve it. Anyways, here is what he gave us.(adsbygoogle = window.adsbygoogle || []).push({});

[tex]

\int_{x}^{xy} f(t) dt[/tex]

This is independent of x.

If [tex]f(2) = 2[/tex], compute the value of

[tex]A(x) = \int_{1}^{x} f(t)dt[/tex]

for all [tex]x > 0[/tex]

He then gave us a hint saying since it is independent of x, the function will be in terms of y.

[tex]g(y) = \int_{x}^{xy}f(t)dt[/tex]

He also told us the final answer is [tex]4 \ln x

[/tex]

Does this make any sense? I would appreciate it if someone can show me how to solve this.

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# Integration Problem I Cannot Figure Out

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