Q. Evaluate ∫6e2+5x−54x−21dx. Write your answer in simplest form with all logs condensed into a single logarithm (if necessary).
Simplify the integrand: Simplify the integrand by dividing the polynomial.We have the integral of a rational function, which can be simplified by polynomial division. The integrand (4x−21)/(x−5) can be divided to get a simpler expression.(4x−21)/(x−5)=4−(1/(x−5))Now, we can write the integral as the sum of two simpler integrals:∫(4x−21)/(x−5)dx=∫4dx−∫(1/(x−5))dx
Integrate the simplified expression: Integrate the simplified expression.The integral of a constant is just the constant times the variable, and the integral of (x−5)1 is the natural logarithm of the absolute value of (x−5).∫4dx=4x∫((x−5)1)dx=ln∣x−5∣So the integral becomes:∫(x−5)(4x−21)dx=4x−ln∣x−5∣+C
Evaluate definite integral: Evaluate the definite integral from x=6 to x=e2+5. We need to evaluate the antiderivative at the upper and lower limits and subtract the lower evaluation from the upper evaluation.At x=e2+5:4x - \ln|x - 5| = 4(e^{2} + 5) - \ln|e^{2} + 5 - 5| = 4e^{2} + 20 - \ln|e^{2}|\(\newlineAt \$x = 6\):\(\newline\)\(4x - \ln|x - 5| = 4(6) - \ln|6 - 5| = 24 - \ln|1|\(\newline\)Now subtract the lower evaluation from the upper evaluation:\(\newline\)\$(4e^{2} + 20 - \ln|e^{2}|) - (24 - \ln|1|)\)\(\newline\)Since \(\ln|1|\) is \(0\), this simplifies to:\(\newline\)\(4e^{2} + 20 - \ln|e^{2}| - 24\)
Simplify and write answer: Simplify the result and write the answer in simplest form.\(\newline\)We can simplify the expression further by recognizing that \(\ln|e^{2}|\) is simply \(2\), since the natural logarithm is the inverse of the exponential function.\(\newline\)\(4e^{2} + 20 - 2 - 24 = 4e^{2} - 6\)\(\newline\)This is the value of the definite integral from \(x=6\) to \(x=e^{2}+5\).
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