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Let the straight line x= b divide the ar...

Let the straight line x= b divide the area enclosed by `y=(1-x)^(2),y=0, and x=0` into two parts `R_(1)(0lexleb) and R_(2)(blexle1)` such that `R_(1)-R_(2)=(1)/(4).` Then b equals

A

`3//4`

B

`1//2`

C

`1//3`

D

`1//4`

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To solve the problem, we need to find the value of \( b \) such that the area \( R_1 \) (from \( x = 0 \) to \( x = b \)) minus the area \( R_2 \) (from \( x = b \) to \( x = 1 \)) equals \( \frac{1}{4} \). ### Step-by-step Solution: 1. **Identify the Area Under the Curve**: The area under the curve \( y = (1 - x)^2 \) from \( x = 0 \) to \( x = 1 \) can be calculated using integration: \[ A = \int_0^1 (1 - x)^2 \, dx \] 2. **Calculate the Total Area**: First, we compute the total area: \[ A = \int_0^1 (1 - x)^2 \, dx = \int_0^1 (1 - 2x + x^2) \, dx \] \[ = \left[ x - x^2 + \frac{x^3}{3} \right]_0^1 = \left( 1 - 1 + \frac{1}{3} \right) - 0 = \frac{1}{3} \] 3. **Set Up the Areas \( R_1 \) and \( R_2 \)**: The area \( R_1 \) from \( x = 0 \) to \( x = b \) is: \[ R_1 = \int_0^b (1 - x)^2 \, dx \] The area \( R_2 \) from \( x = b \) to \( x = 1 \) is: \[ R_2 = \int_b^1 (1 - x)^2 \, dx \] 4. **Calculate \( R_1 \)**: \[ R_1 = \int_0^b (1 - x)^2 \, dx = \left[ x - x^2 + \frac{x^3}{3} \right]_0^b = \left( b - b^2 + \frac{b^3}{3} \right) - 0 = b - b^2 + \frac{b^3}{3} \] 5. **Calculate \( R_2 \)**: \[ R_2 = \int_b^1 (1 - x)^2 \, dx = \int_0^1 (1 - x)^2 \, dx - \int_0^b (1 - x)^2 \, dx \] \[ = \frac{1}{3} - R_1 = \frac{1}{3} - \left( b - b^2 + \frac{b^3}{3} \right) \] 6. **Set Up the Equation**: We are given that \( R_1 - R_2 = \frac{1}{4} \): \[ R_1 - R_2 = \left( b - b^2 + \frac{b^3}{3} \right) - \left( \frac{1}{3} - (b - b^2 + \frac{b^3}{3}) \right) = \frac{1}{4} \] 7. **Simplify the Equation**: This simplifies to: \[ 2(b - b^2 + \frac{b^3}{3}) - \frac{1}{3} = \frac{1}{4} \] \[ 2b - 2b^2 + \frac{2b^3}{3} - \frac{1}{3} = \frac{1}{4} \] 8. **Combine Terms**: Rearranging gives: \[ 2b - 2b^2 + \frac{2b^3}{3} = \frac{1}{4} + \frac{1}{3} \] \[ = \frac{3 + 4}{12} = \frac{7}{12} \] 9. **Final Equation**: Multiply through by 12 to eliminate the fraction: \[ 24b - 24b^2 + 8b^3 = 7 \] Rearranging gives: \[ 8b^3 - 24b^2 + 24b - 7 = 0 \] 10. **Solve for \( b \)**: Using numerical methods or graphing, we find that \( b = \frac{1}{2} \) is a solution. ### Final Answer: Thus, the value of \( b \) is: \[ b = \frac{1}{2} \]

To solve the problem, we need to find the value of \( b \) such that the area \( R_1 \) (from \( x = 0 \) to \( x = b \)) minus the area \( R_2 \) (from \( x = b \) to \( x = 1 \)) equals \( \frac{1}{4} \). ### Step-by-step Solution: 1. **Identify the Area Under the Curve**: The area under the curve \( y = (1 - x)^2 \) from \( x = 0 \) to \( x = 1 \) can be calculated using integration: \[ A = \int_0^1 (1 - x)^2 \, dx ...
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