Question

if a+c=4b,then the roots of ax²+4bx+c=0 are​

Answer 1

Answer:

(4a + c)² <4b²

⇒ 4a + c < ±2b

⇒ 4a + 2b + c < 0

..4a + 2b + c <0

or, 4a2b + c <0

let f(x) = ax² + bx+c

.. f(2)=4a + 2b+c≤ 0 f(-2) = 4a - 2b + c ≤ 0

Case 1: a > 0

Case 2 a 0

...Roots should lie between (-2,2)