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If x=(5)/(3) and x=-(1)/(2) are the zero...

If `x=(5)/(3)` and `x=-(1)/(2)` are the zeroes of the polynomial `ax^(2)-7x+b`, then find the values of a and b.

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To find the values of \( a \) and \( b \) for the polynomial \( ax^2 - 7x + b \) given the roots \( x = \frac{5}{3} \) and \( x = -\frac{1}{2} \), we can follow these steps: ### Step 1: Identify the roots The roots of the polynomial are given as: - \( \alpha = \frac{5}{3} \) - \( \beta = -\frac{1}{2} \) ### Step 2: Calculate \( \alpha + \beta \) To find \( \alpha + \beta \): \[ \alpha + \beta = \frac{5}{3} + \left(-\frac{1}{2}\right) \] To add these fractions, we need a common denominator. The least common multiple of 3 and 2 is 6. \[ \alpha + \beta = \frac{5 \times 2}{3 \times 2} + \left(-\frac{1 \times 3}{2 \times 3}\right) = \frac{10}{6} - \frac{3}{6} = \frac{7}{6} \] ### Step 3: Calculate \( \alpha \beta \) Now, calculate \( \alpha \beta \): \[ \alpha \beta = \frac{5}{3} \times \left(-\frac{1}{2}\right) = -\frac{5}{6} \] ### Step 4: Write the polynomial in terms of its roots The polynomial with roots \( \alpha \) and \( \beta \) can be expressed as: \[ x^2 - (\alpha + \beta)x + \alpha \beta = 0 \] Substituting the values we found: \[ x^2 - \left(\frac{7}{6}\right)x - \frac{5}{6} = 0 \] ### Step 5: Multiply through by 6 to eliminate fractions To eliminate the fractions, multiply the entire equation by 6: \[ 6x^2 - 7x - 5 = 0 \] ### Step 6: Compare with the given polynomial The given polynomial is: \[ ax^2 - 7x + b = 0 \] Comparing coefficients, we find: - Coefficient of \( x^2 \): \( a = 6 \) - Constant term: \( b = -5 \) ### Final Answer Thus, the values of \( a \) and \( b \) are: \[ a = 6, \quad b = -5 \]

To find the values of \( a \) and \( b \) for the polynomial \( ax^2 - 7x + b \) given the roots \( x = \frac{5}{3} \) and \( x = -\frac{1}{2} \), we can follow these steps: ### Step 1: Identify the roots The roots of the polynomial are given as: - \( \alpha = \frac{5}{3} \) - \( \beta = -\frac{1}{2} \) ### Step 2: Calculate \( \alpha + \beta \) ...
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NAGEEN PRAKASHAN-POLYNOMIALS-Exercise 2a
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  2. From question number 1 to 16, find zeroes of the given quadratic polyn...

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  5. From question number 1 to 16, find zeroes of the given quadratic polyn...

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  6. From question number 1 to 16, find zeroes of the given quadratic polyn...

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  7. Find zeroes of the given quadratic polynomials and verify the relation...

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  8. From question number 1 to 16, find zeroes of the given quadratic polyn...

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  9. Find the quadratic polynomial, the sum of whose zeroes is 17 and the p...

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  10. Find a quadratic polynomial, the sum of whose zeroes is 7 and the prod...

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  11. If the product of zeroes of the polynomial 3x^(2)+5x+k is 6, find the ...

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  12. If the sum of zeroes of the polynomial x^(2)+2kx-12 is 1, find the val...

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  13. If x=(5)/(3) and x=-(1)/(2) are the zeroes of the polynomial ax^(2)-7x...

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  14. Find a quadratic polynomial, the sum of whose zeroes is (5)/(3) and pr...

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  15. Find a quadratic polynomial, the sum of whose zeroes is -(3)/(4) and p...

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  16. If alpha, beta be the zeros of the polynomial 2x^(2)+5x+k such that...

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  17. If alpha andbeta are zeroes of a polynomial f(x0=3x^(2)-4x+1, finda qu...

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  18. If alpha,beta are zeroes of the polynomial x^2-2x-15 , then form a qua...

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  19. If alpha and beta are zeroes of a quadratic polynomial ax^(2)+bx+c. Fi...

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  20. Which of the graphs given below corresponds to linear polynomial or a ...

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