Improper Integrals and the Comparison Theorem

Lanza52
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Use the Comparisom Theorem to determine if

f(x) = \int^{\infty}_{42} \frac{42+42^-x}{x}dx

is convergent or divergent.

I compared it to g(x)=\int^{\infty}_{42} \frac{1}{x}dx

\int^{\infty}_{42} \frac{1}{x}dx = Lim_{t->\infty}\int^{t}_{42} \frac{1}{x}dx

Take the antiderivative, and the limit as t approaches infinity of ln(t)-ln(42) is infinity.

So divergent.

Looking for check. Thanks =P
 
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Yes that is correct.
 
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