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Evaluate int(5)^(7)ln(x-3)^(2)dx+2int(0)...

Evaluate `int_(5)^(7)ln(x-3)^(2)dx+2int_(0)^(1)ln(x+4)^(2)dx`

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To evaluate the integral \( \int_{5}^{7} \ln(x-3)^{2} \, dx + 2 \int_{0}^{1} \ln(x+4)^{2} \, dx \), we can follow these steps: ### Step 1: Rewrite the integrals using properties of logarithms Using the property \( \ln(a^b) = b \ln(a) \), we can rewrite the integrals: \[ \int_{5}^{7} \ln(x-3)^{2} \, dx = 2 \int_{5}^{7} \ln(x-3) \, dx \] \[ 2 \int_{0}^{1} \ln(x+4)^{2} \, dx = 4 \int_{0}^{1} \ln(x+4) \, dx \] Thus, the expression becomes: \[ 2 \int_{5}^{7} \ln(x-3) \, dx + 4 \int_{0}^{1} \ln(x+4) \, dx \] ### Step 2: Evaluate the first integral \( \int \ln(x-3) \, dx \) Using integration by parts, let: - \( u = \ln(x-3) \) then \( du = \frac{1}{x-3} \, dx \) - \( dv = dx \) then \( v = x \) Applying integration by parts: \[ \int \ln(x-3) \, dx = x \ln(x-3) - \int \frac{x}{x-3} \, dx \] Now, simplify \( \int \frac{x}{x-3} \, dx \): \[ \int \frac{x}{x-3} \, dx = \int \left( 1 + \frac{3}{x-3} \right) \, dx = x + 3 \ln(x-3) \] Thus, we have: \[ \int \ln(x-3) \, dx = x \ln(x-3) - (x + 3 \ln(x-3)) = (x - 3) \ln(x-3) - x \] ### Step 3: Evaluate the definite integral from 5 to 7 Now we compute: \[ \int_{5}^{7} \ln(x-3) \, dx = \left[ (x-3) \ln(x-3) - x \right]_{5}^{7} \] Calculating at the limits: - At \( x = 7 \): \[ (7-3) \ln(7-3) - 7 = 4 \ln(4) - 7 \] - At \( x = 5 \): \[ (5-3) \ln(5-3) - 5 = 2 \ln(2) - 5 \] Thus: \[ \int_{5}^{7} \ln(x-3) \, dx = \left[ 4 \ln(4) - 7 \right] - \left[ 2 \ln(2) - 5 \right] \] Simplifying this gives: \[ = 4 \ln(4) - 2 \ln(2) - 2 \] Using \( \ln(4) = 2 \ln(2) \): \[ = 4(2 \ln(2)) - 2 \ln(2) - 2 = 8 \ln(2) - 2 \ln(2) - 2 = 6 \ln(2) - 2 \] ### Step 4: Evaluate the second integral \( \int \ln(x+4) \, dx \) Using integration by parts again: Let: - \( u = \ln(x+4) \) then \( du = \frac{1}{x+4} \, dx \) - \( dv = dx \) then \( v = x \) Thus: \[ \int \ln(x+4) \, dx = x \ln(x+4) - \int \frac{x}{x+4} \, dx \] Simplifying \( \int \frac{x}{x+4} \, dx \): \[ \int \frac{x}{x+4} \, dx = \int \left( 1 - \frac{4}{x+4} \right) \, dx = x - 4 \ln(x+4) \] So: \[ \int \ln(x+4) \, dx = x \ln(x+4) - (x - 4 \ln(x+4)) = 5 \ln(x+4) - x \] ### Step 5: Evaluate the definite integral from 0 to 1 Now compute: \[ \int_{0}^{1} \ln(x+4) \, dx = \left[ 5 \ln(x+4) - x \right]_{0}^{1} \] Calculating at the limits: - At \( x = 1 \): \[ 5 \ln(1+4) - 1 = 5 \ln(5) - 1 \] - At \( x = 0 \): \[ 5 \ln(0+4) - 0 = 5 \ln(4) \] Thus: \[ \int_{0}^{1} \ln(x+4) \, dx = (5 \ln(5) - 1) - 5 \ln(4) = 5 \ln(5) - 5 \ln(4) - 1 \] Using \( \ln(4) = 2 \ln(2) \): \[ = 5(\ln(5) - 2 \ln(2)) - 1 \] ### Step 6: Combine results Now substitute back into the original expression: \[ 2 \int_{5}^{7} \ln(x-3) \, dx + 4 \int_{0}^{1} \ln(x+4) \, dx \] This becomes: \[ 2(6 \ln(2) - 2) + 4(5(\ln(5) - 2 \ln(2)) - 1) \] Calculating: \[ = 12 \ln(2) - 4 + 20 \ln(5) - 8 \ln(2) - 4 = 4 \ln(2) + 20 \ln(5) - 8 \] ### Final Answer Thus, the final result is: \[ 4 \ln(2) + 20 \ln(5) - 8 \]
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