Q. Evaluate ∫612x−5x−7dx. Write your answer in simplest form with all logs condensed into a single logarithm (if necessary).Submit Answer
Simplify the integrand: Simplify the integrand.We have the integrand (x−7)/(x−5). We can perform long division or recognize that this is a proper rational function that can be decomposed into a sum of simpler fractions. We can write (x−7)/(x−5) as 1−2/(x−5).
Set up the integral: Set up the integral with the simplified integrand.Now we can write the integral as:∫612(1−x−52)dxThis separates into two simpler integrals:∫6121dx−∫612x−52dx
Evaluate first integral: Evaluate the first integral.The integral of 1 with respect to x from 6 to 12 is simply x evaluated from 6 to 12:∫6121dx=[x]612=12−6=6
Evaluate second integral: Evaluate the second integral.The integral of x−52 with respect to x from 6 to 12 is 2 times the natural logarithm of the absolute value of (x−5) evaluated from 6 to 12:∫612x−52dx=2×[ln∣x−5∣]612=2×(ln∣12−5∣−ln∣6−5∣)=2×(ln∣7∣−ln∣1∣)x0
Combine results: Combine the results from Step 3 and Step 4.The final answer is the difference between the two results:6−2×ln(7)
Write final answer: Write the answer in simplest form.Since ln(1) is 0, we can simplify the expression to:6−2×ln(7)This is already in simplest form with the logarithm condensed into a single term.
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