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If the equation x^(2)+4x+k=0 has real an...

If the equation `x^(2)+4x+k=0` has real and distinct roots, then find the value of 'k'.

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To determine the value of \( k \) for which the quadratic equation \( x^2 + 4x + k = 0 \) has real and distinct roots, we need to use the discriminant condition. ### Step 1: Identify the coefficients In the quadratic equation \( ax^2 + bx + c = 0 \), we have: - \( a = 1 \) - \( b = 4 \) - \( c = k \) ### Step 2: Write the discriminant condition The discriminant \( D \) of a quadratic equation is given by the formula: \[ D = b^2 - 4ac \] For the roots to be real and distinct, the discriminant must be greater than zero: \[ D > 0 \] ### Step 3: Substitute the coefficients into the discriminant formula Substituting \( a \), \( b \), and \( c \) into the discriminant formula, we get: \[ D = 4^2 - 4 \cdot 1 \cdot k \] This simplifies to: \[ D = 16 - 4k \] ### Step 4: Set up the inequality For the roots to be real and distinct, we need: \[ 16 - 4k > 0 \] ### Step 5: Solve the inequality Rearranging the inequality gives: \[ 16 > 4k \] Dividing both sides by 4: \[ 4 > k \] or \[ k < 4 \] ### Conclusion The value of \( k \) must be less than 4 for the quadratic equation \( x^2 + 4x + k = 0 \) to have real and distinct roots.
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EDUCART PUBLICATION-SAMPLE PAPER 7-PART - A (SECTION - I)
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  2. Find the area of figure given below.

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