If one root of a quadratic equation 3x2+ PX + 4 = 0 is 2/3, find the value of p
The given equation is
3x2 + px + 4 = 0
since x = 2/3 is a root of the above equation, then it must satisfy it.
3(2/3)2 + 2p/3 + 4 = 0
⇒ 4/3 + 4 + 2p/3 = 0
⇒ 2p/3 = -4/3 - 4
⇒ 2p = -16
⇒ p = - 8