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Evaluate 
int_(3)^(7)(4x^(2)-5x-12)/(x+1)dx. Write your answer in simplest form with all logs condensed into a single logarithm (if necessary).

Evaluate 374x25x12x+1dx \int_{3}^{7} \frac{4 x^{2}-5 x-12}{x+1} d x . Write your answer in simplest form with all logs condensed into a single logarithm (if necessary).

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Q. Evaluate 374x25x12x+1dx \int_{3}^{7} \frac{4 x^{2}-5 x-12}{x+1} d x . Write your answer in simplest form with all logs condensed into a single logarithm (if necessary).
  1. Perform polynomial long division: Perform polynomial long division to simplify the integrand.\newlineWe need to divide the polynomial 4x25x124x^2 - 5x - 12 by x+1x + 1.
  2. Polynomial long division calculation: Polynomial long division calculation.\newline(4x25x12)÷(x+1)=4x93(x+1)(4x^2 - 5x - 12) \div (x + 1) = 4x - 9 - \frac{3}{(x + 1)}\newlineNow we can rewrite the integral as:\newline37(4x93(x+1))dx\int_{3}^{7} (4x - 9 - \frac{3}{(x + 1)}) dx
  3. Split into three integrals: Split the integral into three separate integrals.\newline\int_{\(3\)}^{\(7\)} (\(4x - 99 - \frac{33}{x + 11}) \, dx = \int_{33}^{77} 44x \, dx - \int_{33}^{77} 99 \, dx - \int_{33}^{77} \frac{33}{x + 11} \, dx
  4. Evaluate each integral separately: Evaluate each integral separately.\newlineFirst integral: 374xdx=2x2\int_{3}^{7} 4x \, dx = 2x^2 | from x=3x = 3 to x=7x = 7\newlineSecond integral: 379dx=9x\int_{3}^{7} 9 \, dx = 9x | from x=3x = 3 to x=7x = 7\newlineThird integral: 373x+1dx=3lnx+1\int_{3}^{7} \frac{3}{x + 1} \, dx = 3\ln|x + 1| | from x=3x = 3 to x=7x = 7
  5. Calculate definite integrals: Calculate the definite integrals using the Fundamental Theorem of Calculus.\newlineFirst integral: 2x22x^2 | from x=3x = 3 to x=7=2(72)2(32)=9818=80x = 7 = 2(7^2) - 2(3^2) = 98 - 18 = 80\newlineSecond integral: 9x9x | from x=3x = 3 to x=7=9(7)9(3)=6327=36x = 7 = 9(7) - 9(3) = 63 - 27 = 36\newlineThird integral: 3lnx+13\ln|x + 1| | from x=3x = 3 to x=7=3ln(7+1)3ln(3+1)=3ln(8)3ln(4)x = 7 = 3\ln(7 + 1) - 3\ln(3 + 1) = 3\ln(8) - 3\ln(4)
  6. Combine integral results: Combine the results from each integral.\newlineTotal integral value = 8036(3ln(8)3ln(4))80 - 36 - (3\ln(8) - 3\ln(4))
  7. Simplify the expression: Simplify the expression.\newlineTotal integral value = 443ln(8)+3ln(4)44 - 3\ln(8) + 3\ln(4)\newlineSince ln(a)ln(b)=ln(ab)\ln(a) - \ln(b) = \ln\left(\frac{a}{b}\right), we can combine the logarithms:\newlineTotal integral value = 443ln(23/22)=443ln(2)44 - 3\ln\left(2^3/2^2\right) = 44 - 3\ln(2)
  8. Write final answer: Write the final answer.\newlineThe integral of (4x25x12)/(x+1)(4x^2 - 5x - 12) / (x + 1) from x=3x = 3 to x=7x = 7 is 443ln(2)44 - 3\ln(2).

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