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If sin^(2)alpha,cos^(2)alphaand-cosec^(2...

If `sin^(2)alpha,cos^(2)alphaand-cosec^(2)alpha` are the zeros of `P(x)=x^(3)+x^(2)+ax+b(a,binR)`. Then P(2) equals ______.

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To solve the problem, we need to find the value of \( P(2) \) for the polynomial \( P(x) = x^3 + x^2 + ax + b \), given that the zeros of the polynomial are \( \sin^2 \alpha \), \( \cos^2 \alpha \), and \( -\csc^2 \alpha \). ### Step 1: Identify the roots and their relationships The roots of the polynomial are: - \( r_1 = \sin^2 \alpha \) - \( r_2 = \cos^2 \alpha \) - \( r_3 = -\csc^2 \alpha \) From the Pythagorean identity, we know: \[ \sin^2 \alpha + \cos^2 \alpha = 1 \] ### Step 2: Calculate the sum of the roots Using Vieta's formulas, the sum of the roots \( r_1 + r_2 + r_3 \) is equal to \( -\frac{\text{coefficient of } x^2}{\text{coefficient of } x^3} \): \[ r_1 + r_2 + r_3 = -1 \] Substituting the known values: \[ \sin^2 \alpha + \cos^2 \alpha - \csc^2 \alpha = -1 \] Since \( \sin^2 \alpha + \cos^2 \alpha = 1 \), we can substitute: \[ 1 - \csc^2 \alpha = -1 \] This simplifies to: \[ -\csc^2 \alpha = -2 \implies \csc^2 \alpha = 2 \] Thus, we have: \[ \sin^2 \alpha = \frac{1}{2} \quad \text{and} \quad \cos^2 \alpha = \frac{1}{2} \] ### Step 3: Substitute the roots into the polynomial Now we can express the polynomial \( P(x) \) in terms of its roots: \[ P(x) = (x - \sin^2 \alpha)(x - \cos^2 \alpha)(x + \csc^2 \alpha) \] Substituting the values of the roots: \[ P(x) = \left(x - \frac{1}{2}\right)\left(x - \frac{1}{2}\right)\left(x + 2\right) \] This simplifies to: \[ P(x) = \left(x - \frac{1}{2}\right)^2 (x + 2) \] ### Step 4: Expand the polynomial First, expand \( \left(x - \frac{1}{2}\right)^2 \): \[ \left(x - \frac{1}{2}\right)^2 = x^2 - x + \frac{1}{4} \] Now multiply by \( (x + 2) \): \[ P(x) = (x^2 - x + \frac{1}{4})(x + 2) \] Expanding this: \[ P(x) = x^3 + 2x^2 - x^2 - 2x + \frac{1}{4}x + \frac{1}{2} \] Combine like terms: \[ P(x) = x^3 + x^2 - \frac{7}{4}x + \frac{1}{2} \] ### Step 5: Evaluate \( P(2) \) Now we substitute \( x = 2 \): \[ P(2) = 2^3 + 2^2 - \frac{7}{4}(2) + \frac{1}{2} \] Calculating each term: \[ = 8 + 4 - \frac{14}{4} + \frac{2}{4} \] \[ = 8 + 4 - \frac{12}{4} \] \[ = 8 + 4 - 3 = 9 \] Thus, the final answer is: \[ \boxed{9} \]

To solve the problem, we need to find the value of \( P(2) \) for the polynomial \( P(x) = x^3 + x^2 + ax + b \), given that the zeros of the polynomial are \( \sin^2 \alpha \), \( \cos^2 \alpha \), and \( -\csc^2 \alpha \). ### Step 1: Identify the roots and their relationships The roots of the polynomial are: - \( r_1 = \sin^2 \alpha \) - \( r_2 = \cos^2 \alpha \) - \( r_3 = -\csc^2 \alpha \) ...
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