Problem

Suppose $\int f(x) d x=\frac{16}{x}+12 \cdot 2^{-x}+16 \tan \left(\frac{\pi}{4 x}\right)+7 \cos \left(\frac{\pi}{2 x}\right)$
Determine $\int_{1}^{\infty} f(x) d x$.
The integral converges to

Answer

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Answer

So, the integral converges to \(\boxed{-31}\)

Steps

Step 1 :Suppose the integral of function f(x) is given by \(\int f(x) d x=\frac{16}{x}+12 \cdot 2^{-x}+16 \tan \left(\frac{\pi}{4 x}\right)+7 \cos \left(\frac{\pi}{2 x}\right)\)

Step 2 :We want to determine the value of \(\int_{1}^{\infty} f(x) d x\)

Step 3 :The integral of a function from 1 to infinity is the limit as b goes to infinity of the integral from 1 to b

Step 4 :We can find the antiderivative of f(x) and evaluate it at 1 and b, then take the limit as b goes to infinity

Step 5 :The antiderivative of f(x) is given in the question

Step 6 :Let's denote the antiderivative as F, so F = \(7\cos(\frac{\pi}{2x}) + 16\tan(\frac{\pi}{4x}) + \frac{16}{x} + \frac{12}{2^x}\)

Step 7 :Taking the limit as b goes to infinity, we find that the value is -31

Step 8 :So, the integral converges to \(\boxed{-31}\)

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