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"Let " k(x)=int((x^(2)+1)dx)/(root(3)(x^...

`"Let " k(x)=int((x^(2)+1)dx)/(root(3)(x^(3)+3x+6)) " and " k(-1)=(1)/(root(3)(2)). " Then the value of " k(-2) " is "-.`

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To solve the problem step by step, we start with the function defined as: \[ k(x) = \frac{\int (x^2 + 1) \, dx}{\sqrt[3]{x^3 + 3x + 6}} \] We are given that \( k(-1) = \frac{1}{\sqrt[3]{2}} \) and we need to find \( k(-2) \). ### Step 1: Substitute \( T \) Let \( T = x^3 + 3x + 6 \). Then, we differentiate \( T \): \[ \frac{dT}{dx} = 3x^2 + 3 \] This implies: \[ dT = (3x^2 + 3) \, dx \] ### Step 2: Rearranging \( dx \) From the above, we can express \( dx \): \[ dx = \frac{dT}{3(x^2 + 1)} \] ### Step 3: Substitute in the Integral Now substitute \( dx \) into the integral: \[ k(x) = \frac{\int (x^2 + 1) \, dx}{\sqrt[3]{T}} \] Substituting for \( dx \): \[ k(x) = \frac{\int (x^2 + 1) \cdot \frac{dT}{3(x^2 + 1)}}{\sqrt[3]{T}} \] The \( (x^2 + 1) \) cancels out: \[ k(x) = \frac{1}{3} \int dT \cdot \frac{1}{\sqrt[3]{T}} \] ### Step 4: Evaluate the Integral The integral simplifies to: \[ k(x) = \frac{1}{3} \cdot \frac{T^{2/3}}{2/3} + C = \frac{T^{2/3}}{2} + C \] ### Step 5: Substitute Back for \( T \) Now substitute back \( T = x^3 + 3x + 6 \): \[ k(x) = \frac{(x^3 + 3x + 6)^{2/3}}{2} + C \] ### Step 6: Use Given Information to Find \( C \) We know \( k(-1) = \frac{1}{\sqrt[3]{2}} \): Substituting \( x = -1 \): \[ k(-1) = \frac{((-1)^3 + 3(-1) + 6)^{2/3}}{2} + C \] Calculating \( (-1)^3 + 3(-1) + 6 = -1 - 3 + 6 = 2 \): \[ k(-1) = \frac{(2)^{2/3}}{2} + C = \frac{2^{2/3}}{2} + C \] Setting this equal to \( \frac{1}{\sqrt[3]{2}} \): \[ \frac{2^{2/3}}{2} + C = \frac{1}{2^{1/3}} \] ### Step 7: Solve for \( C \) To solve for \( C \): \[ C = \frac{1}{2^{1/3}} - \frac{2^{2/3}}{2} \] ### Step 8: Calculate \( k(-2) \) Now we need to find \( k(-2) \): Substituting \( x = -2 \): \[ k(-2) = \frac{((-2)^3 + 3(-2) + 6)^{2/3}}{2} + C \] Calculating \( (-2)^3 + 3(-2) + 6 = -8 - 6 + 6 = -8 \): \[ k(-2) = \frac{(-8)^{2/3}}{2} + C \] Calculating \( (-8)^{2/3} = (8^{2/3}) = 4 \): \[ k(-2) = \frac{4}{2} + C = 2 + C \] ### Step 9: Substitute \( C \) Now substitute \( C \) back into the equation: \[ k(-2) = 2 + \left( \frac{1}{2^{1/3}} - \frac{2^{2/3}}{2} \right) \] ### Final Calculation Calculating the final value: \[ k(-2) = 2 + \frac{1}{2^{1/3}} - \frac{2^{2/3}}{2} \] This gives us the final value of \( k(-2) \).

To solve the problem step by step, we start with the function defined as: \[ k(x) = \frac{\int (x^2 + 1) \, dx}{\sqrt[3]{x^3 + 3x + 6}} \] We are given that \( k(-1) = \frac{1}{\sqrt[3]{2}} \) and we need to find \( k(-2) \). ### Step 1: Substitute \( T \) Let \( T = x^3 + 3x + 6 \). Then, we differentiate \( T \): ...
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