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If the sum of the zeroes of the quadrati...

If the sum of the zeroes of the quadratic polynomial   f(x) = `mx^(2) + 2x + 3m`   is equal to their product, then m equals

A

`1/3`

B

`2/3`

C

`-2/3`

D

`-1/3`

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to find the value of \( m \) such that the sum of the zeroes of the quadratic polynomial \( f(x) = mx^2 + 2x + 3m \) is equal to their product. ### Step 1: Identify the coefficients The given polynomial is in the standard form \( ax^2 + bx + c \), where: - \( a = m \) - \( b = 2 \) - \( c = 3m \) ### Step 2: Use the formulas for the sum and product of the roots For a quadratic polynomial \( ax^2 + bx + c \): - The sum of the roots \( \alpha + \beta \) is given by \( -\frac{b}{a} \) - The product of the roots \( \alpha \beta \) is given by \( \frac{c}{a} \) ### Step 3: Calculate the sum of the roots Using the coefficients identified: \[ \text{Sum of the roots} = \alpha + \beta = -\frac{b}{a} = -\frac{2}{m} \] ### Step 4: Calculate the product of the roots \[ \text{Product of the roots} = \alpha \beta = \frac{c}{a} = \frac{3m}{m} = 3 \] ### Step 5: Set up the equation According to the problem, the sum of the roots is equal to their product: \[ -\frac{2}{m} = 3 \] ### Step 6: Solve for \( m \) To solve for \( m \), we can multiply both sides by \( m \) (assuming \( m \neq 0 \)): \[ -2 = 3m \] Now, divide both sides by 3: \[ m = -\frac{2}{3} \] ### Conclusion The value of \( m \) is \( -\frac{2}{3} \). ---
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