Question

(c) The value of k for which the roots of Qaudratic equations x² + 4x + k = 0 are real is __________ .​

Answer 1

Answer:

k ∈ (-∞,4]

Step-by-step explanation:

For the roots of the quadratic equation to be real D≥0

D = b² - 4ac

D = 16 - 4k

To roots to be real D≥0

16 - 4k≥0

-4k≥-16

4k≤16

k≤4