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Evaluate 
int_(1)^(3)(4x^(2)-19 x+9)/(x-4)dx. Write your answer in simplest form with all logs condensed into a single logarithm (if necessary).

Evaluate 134x219x+9x4dx \int_{1}^{3} \frac{4 x^{2}-19 x+9}{x-4} d x . Write your answer in simplest form with all logs condensed into a single logarithm (if necessary).

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Q. Evaluate 134x219x+9x4dx \int_{1}^{3} \frac{4 x^{2}-19 x+9}{x-4} d x . Write your answer in simplest form with all logs condensed into a single logarithm (if necessary).
  1. Perform Polynomial Long Division: First, we will perform polynomial long division to simplify the integrand (4x219x+9)/(x4)(4x^2 - 19x + 9)/(x - 4). Dividing 4x24x^2 by xx gives us 4x4x. Multiplying 4x4x by (x4)(x - 4) gives us 4x216x4x^2 - 16x. Subtracting this from the original numerator, we get 19x+9(4x216x)=3x+9-19x + 9 - (4x^2 - 16x) = -3x + 9. Dividing 3x-3x by xx gives us 4x24x^200. Multiplying 4x24x^200 by (x4)(x - 4) gives us 4x24x^233. Subtracting this from the previous remainder, we get 4x24x^244. Since 4x24x^255 is of lower degree than the divisor 4x24x^266, we stop here. The result of the division is 4x24x^277 with a remainder of 4x24x^255. So, the integrand can be rewritten as 4x24x^299.
  2. Split Integral into Two Parts: Now, we can split the integral into two parts: 13(4x3)dx\int_{1}^{3}(4x - 3)\,dx and 133x3x4dx\int_{1}^{3}\frac{3x - 3}{x - 4}\,dx. The first integral is straightforward to evaluate: (4x3)dx=2x23x+C\int(4x - 3)\,dx = 2x^2 - 3x + C. Evaluating from 11 to 33 gives us (2(3)23(3))(2(1)23(1))=(189)(23)=9+1=10(2(3)^2 - 3(3)) - (2(1)^2 - 3(1)) = (18 - 9) - (2 - 3) = 9 + 1 = 10.
  3. Evaluate First Integral: The second integral (3x3)/(x4)dx\int(3x - 3)/(x - 4)dx from 11 to 33 is more complex. We can rewrite the numerator to match the derivative of the denominator:\newlineLet's rewrite 3x33x - 3 as 3(x4)+123(x - 4) + 12, so the integral becomes (3(x4)+12)/(x4)dx\int(3(x - 4) + 12)/(x - 4)dx.\newlineThis can be split into two integrals: 3(x4)/(x4)dx+121/(x4)dx3\int(x - 4)/(x - 4)dx + 12\int1/(x - 4)dx.\newlineThe first part simplifies to 31dx3\int1dx, which is just 3x3x.\newlineThe second part is 121/(x4)dx12\int1/(x - 4)dx, which is 1100.
  4. Rewrite Numerator for Second Integral: Now we can evaluate the second integral from 11 to 33: 13dx\int_{1}^{3}dx from 11 to 33 is simply 3x3x evaluated from 11 to 33, which gives us 3(3)3(1)=93=63(3) - 3(1) = 9 - 3 = 6. 1312x4dx\int_{1}^{3}\frac{12}{x - 4}dx from 11 to 33 is 3322 evaluated from 11 to 33, which gives us 3355. Since 3366 is 3377, this simplifies to 3388.
  5. Evaluate Second Integral: Combining the results from the two parts of the integral, we have:\newlineThe integral from 11 to 33 of (4x219x+9)/(x4)(4x^2 - 19x + 9)/(x - 4)dx is equal to 1010 (from the first part) plus 66 (from the second part, the 3x3x term) minus 12ln(3)12\ln(3) (from the second part, the logarithmic term).\newlineSo, the final answer is 1612ln(3)16 - 12\ln(3).

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