Home
Class 10
MATHS
If (2)/(3) and -(1)/(2) are solution of ...

If `(2)/(3)` and `-(1)/(2)` are solution of quadratic equation `6x^(2)+ax-b=0`, find the values of a and b.

Text Solution

AI Generated Solution

The correct Answer is:
To find the values of \( a \) and \( b \) in the quadratic equation \( 6x^2 + ax - b = 0 \) given that the solutions are \( \frac{2}{3} \) and \( -\frac{1}{2} \), we can follow these steps: ### Step 1: Identify the roots Let the roots of the quadratic equation be \( \alpha = \frac{2}{3} \) and \( \beta = -\frac{1}{2} \). ### Step 2: Calculate the sum of the roots The sum of the roots \( \alpha + \beta \) can be calculated as follows: \[ \alpha + \beta = \frac{2}{3} + \left(-\frac{1}{2}\right) \] To add these fractions, we need a common denominator. The least common multiple of 3 and 2 is 6. \[ \alpha + \beta = \frac{2 \times 2}{6} + \left(-\frac{1 \times 3}{6}\right) = \frac{4}{6} - \frac{3}{6} = \frac{1}{6} \] ### Step 3: Calculate the product of the roots The product of the roots \( \alpha \beta \) is calculated as follows: \[ \alpha \beta = \frac{2}{3} \times \left(-\frac{1}{2}\right) = -\frac{2}{6} = -\frac{1}{3} \] ### Step 4: Form the quadratic equation using the roots Using the sum and product of the roots, we can write the quadratic equation in the form: \[ x^2 - (\alpha + \beta)x + \alpha \beta = 0 \] Substituting the values we found: \[ x^2 - \left(\frac{1}{6}\right)x - \left(-\frac{1}{3}\right) = 0 \] This simplifies to: \[ x^2 - \frac{1}{6}x + \frac{1}{3} = 0 \] ### Step 5: Eliminate the fractions To eliminate the fractions, multiply the entire equation by 6: \[ 6x^2 - x + 2 = 0 \] ### Step 6: Compare with the original equation Now we compare this equation \( 6x^2 - x + 2 = 0 \) with the given equation \( 6x^2 + ax - b = 0 \): - From \( -x \), we have \( a = -1 \) - From \( +2 \), we have \( b = 2 \) ### Final Values Thus, the values of \( a \) and \( b \) are: \[ a = -1, \quad b = 2 \]
Promotional Banner

Topper's Solved these Questions

  • QUADRATIC EQUATIONS

    ICSE|Exercise Exercise 5(A)|5 Videos
  • QUADRATIC EQUATIONS

    ICSE|Exercise Exercise 5(B)|5 Videos
  • PROBABILITY

    ICSE|Exercise EXERCISE 25(C)|106 Videos
  • QUESTION PAPER 2019

    ICSE|Exercise SECTION B |20 Videos

Similar Questions

Explore conceptually related problems

If x=-3 and x=(2)/(3) are solution of quadratic equation mx^(2)+7x+n=0 , find the values of m and n.

If x=-(1)/(2) is a solution of the quadratic equation 3x^(2)+2kx-3=0 , find the velue of k.

If x=(2)/(3) is a solution of the quadratic equation 7x^(2)+mx-3=0 , find the value of m.

If x=(-1)/2 , is a solution of the quadratic equation 3x^2+2k x-3=0 , find the value of k .

If x=1(1)/(2) is a solution of the equation 2x^(2)+px-6=0 , find the value of 'p'.

Root of the quadratic equation x^2+6x-2=0

If 3 and -3 are the solutions of equation ax^(2)+bx-9=0 , find the values of a and b.

If one root of the quadratic equation 6x^(2)-x-k=0" is" (2)/(3) , then find the value of k.