Question

If the equation x² + 5kx + 16 = 0 has no real roots then

पर्याय

• `k > 8/5`

• `k < (-8)/5`

• `(-8)/5 < k < 8/5`

• none of these

Answer 1

`bb((-8)/5 < k < 8/5)`

Explanation:

It is given that the equation (x² + 5kx + 16 = 0) has no real roots.  

∴ (b² – 4ac) < 0

⇒ (5k)² – 4 × 1 × 16 < 0 

⇒ 25k² – 64 < 0 

⇒ `k^2 < 64/25` 

⇒ `(-8)/5 < k < 8/5`