If the equation x2 + 4x + k = 0 has real and distinct roots, then

If roots of given equation are real and distinct then D = b2 – 4ac > 0

Here a = 1, b = 4 and c = k


So, 42 – 4 (1) (k) >0


16 – 4k > 0


16 > 4k


K< 4

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