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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 \( b \) in the polynomial \( ax^2 - 7x + b \) given that the zeroes are \( x = \frac{5}{3} \) 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: Use the relationship between roots and coefficients For a quadratic polynomial \( x^2 - (\alpha + \beta)x + \alpha \beta = 0 \), we can express the polynomial in terms of its roots: - The sum of the roots \( \alpha + \beta \) is: \[ \alpha + \beta = \frac{5}{3} + \left(-\frac{1}{2}\right) = \frac{5}{3} - \frac{1}{2} \] To add these fractions, we need a common denominator, which is 6: \[ \frac{5}{3} = \frac{10}{6}, \quad -\frac{1}{2} = -\frac{3}{6} \] Therefore, \[ \alpha + \beta = \frac{10}{6} - \frac{3}{6} = \frac{7}{6} \] - The product of the roots \( \alpha \beta \) is: \[ \alpha \beta = \frac{5}{3} \cdot \left(-\frac{1}{2}\right) = -\frac{5}{6} \] ### Step 3: Form the polynomial using the roots Using the roots, we can write the polynomial as: \[ x^2 - \left(\frac{7}{6}\right)x - \left(-\frac{5}{6}\right) = 0 \] This simplifies to: \[ x^2 - \frac{7}{6}x - \frac{5}{6} = 0 \] ### Step 4: Eliminate the fractions To eliminate the fractions, we multiply the entire equation by 6: \[ 6x^2 - 7x - 5 = 0 \] ### Step 5: Compare coefficients Now we compare this polynomial with the given polynomial \( ax^2 - 7x + b \): - From \( 6x^2 \), we see that \( a = 6 \). - From \( -5 \), we see that \( b = -5 \). ### Final Answer Thus, the values of \( a \) and \( b \) are: \[ a = 6, \quad b = -5 \]

To find the values of \( a \) and \( b \) in the polynomial \( ax^2 - 7x + b \) given that the zeroes are \( x = \frac{5}{3} \) 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: Use the relationship between roots and coefficients ...
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NAGEEN PRAKASHAN ENGLISH-POLYNOMIALS-Exercise 2a
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  2. Find zeroes of the given quadratic polynomials and verify the relation...

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

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  8. find zeroes of the given quadratic polynomials and verify the relation...

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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 and beta are the zeros of the polynomial f(x)=2x^2+5x+k satis...

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  17. If alpha and beta are the zeros of the quadratic polynomial f(x)=3x...

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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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