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Which of the following are the roots of ...

Which of the following are the roots of `3x^(2)+2x-1=0`?
(i) `-1" "(ii)" "(1)/(3)" "(iii)" "-(1)/(2)`

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To determine which of the given options are the roots of the quadratic equation \(3x^2 + 2x - 1 = 0\), we will substitute each option into the equation and check if it satisfies the equation. ### Step-by-Step Solution: 1. **Substituting \(x = -1\)**: \[ 3(-1)^2 + 2(-1) - 1 = 3(1) - 2 - 1 = 3 - 2 - 1 = 0 \] Since the left-hand side equals 0, \(x = -1\) is a root. 2. **Substituting \(x = \frac{1}{3}\)**: \[ 3\left(\frac{1}{3}\right)^2 + 2\left(\frac{1}{3}\right) - 1 = 3\left(\frac{1}{9}\right) + \frac{2}{3} - 1 = \frac{1}{3} + \frac{2}{3} - 1 = 1 - 1 = 0 \] Since the left-hand side equals 0, \(x = \frac{1}{3}\) is also a root. 3. **Substituting \(x = -\frac{1}{2}\)**: \[ 3\left(-\frac{1}{2}\right)^2 + 2\left(-\frac{1}{2}\right) - 1 = 3\left(\frac{1}{4}\right) - 1 - 1 = \frac{3}{4} - 1 - 1 = \frac{3}{4} - \frac{4}{4} - \frac{4}{4} = \frac{3 - 4 - 4}{4} = \frac{-5}{4} \neq 0 \] Since the left-hand side does not equal 0, \(x = -\frac{1}{2}\) is not a root. ### Conclusion: The roots of the equation \(3x^2 + 2x - 1 = 0\) are \(x = -1\) and \(x = \frac{1}{3}\). Therefore, the correct options are (i) and (ii).
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RS AGGARWAL-QUADRATIC EQUATIONS -Exercise 4A
  1. Which of the following are quadratic equations in x? (i)" "x^(2)-x+...

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  2. Which of the following are the roots of 3x^(2)+2x-1=0? (i) -1" ...

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  3. (i) Find the value of k for which x=1 is a root of the equation x^(2)+...

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  4. Show that x=-(bc)/(ad) is a solution of the quadratic equation ad^(2)(...

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  5. Solve each of the following quadratic equations: (2x-3)(3x+1)=0

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  6. Solve each of the following quadratic equations: 4x^(2)+5x=0

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  7. Solve each of the following quadratic equations: 3x^(2)-243=0

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  8. Solve each of the following quadratic equations: 2x^(2)+x-6=0

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  9. Solve each of the following quadratic equations: x^(2)+6x+5=0

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  10. Solve each of the following quadratic equations: 9x^(2)-3x-2=0

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  11. Solve each of the following quadratic equations: x^(2)+12x+35=0

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  12. Solve each of the following quadratic equations: x^(2)=18x-77

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  13. Solve each of the following quadratic equations: 6x^(2)+11x+3=0

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  14. Solve each of the following quadratic equations: 6x^(2)+x-12=0

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  15. Solve each of the following quadratic equations: 3x^(2)-2x-1=0

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  16. Solve each of the following quadratic equations: 4x^(2)-9x=100

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  17. Solve each of the following quadratic equations: 15x^(2)-28=x

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  18. Solve each of the following quadratic equations: 4-11x=3x^(2)

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  19. Solve each of the following equatins : 48x^(2)-13x-1=0

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  20. Solve the following quadratic equations by factorization method. x^2+2...

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