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For what value of 'k' will the equation ...

For what value of 'k' will the equation `2k x ^(2) -2 (1+2k)x + (3 +2k) =0` have real but distinct roots ? When will the roots be equal ?

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To determine the value of 'k' for which the equation \(2k x^2 - 2(1 + 2k)x + (3 + 2k) = 0\) has real but distinct roots, we need to analyze the discriminant of the quadratic equation. The discriminant \(d\) is given by the formula: \[ d = b^2 - 4ac \] ### Step 1: Identify coefficients In our equation, we can identify: - \(a = 2k\) - \(b = -2(1 + 2k)\) - \(c = 3 + 2k\) ### Step 2: Calculate the discriminant Now, we will calculate the discriminant \(d\): \[ d = (-2(1 + 2k))^2 - 4(2k)(3 + 2k) \] Calculating \(b^2\): \[ b^2 = (-2(1 + 2k))^2 = 4(1 + 2k)^2 = 4(1 + 4k + 4k^2) = 4 + 16k + 16k^2 \] Calculating \(4ac\): \[ 4ac = 4(2k)(3 + 2k) = 8k(3 + 2k) = 24k + 16k^2 \] ### Step 3: Substitute in the discriminant formula Now substituting \(b^2\) and \(4ac\) into the discriminant formula: \[ d = (4 + 16k + 16k^2) - (24k + 16k^2) \] ### Step 4: Simplify the discriminant Now, simplifying the expression: \[ d = 4 + 16k + 16k^2 - 24k - 16k^2 \] \[ d = 4 - 8k \] ### Step 5: Set the condition for real and distinct roots For the roots to be real and distinct, we need: \[ d > 0 \] \[ 4 - 8k > 0 \] ### Step 6: Solve the inequality Now, solving the inequality: \[ 4 > 8k \] \[ \frac{4}{8} > k \] \[ \frac{1}{2} > k \] Thus, we have: \[ k < \frac{1}{2} \] ### Step 7: Condition for equal roots For the roots to be equal, we set the discriminant equal to zero: \[ d = 0 \] \[ 4 - 8k = 0 \] ### Step 8: Solve for k Solving for \(k\): \[ 4 = 8k \] \[ k = \frac{4}{8} = \frac{1}{2} \] ### Final Answer Thus, the value of \(k\) for which the equation has real but distinct roots is \(k < \frac{1}{2}\), and the roots will be equal when \(k = \frac{1}{2}\). ---
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