QUADRATIC EQUATIONS - COMMON ROOTS OF TWO QUADRATIC EQUATIONS

QUADRATIC EQUATIONS

a. Only one common root

Let be the common root of then 

 

By Cramer's Rule 

Therefore ,

So the condition for a common root is

 

b.

If both roots are same then

 

 

Example :

 

Find p and q such that px2 +5x+2=0 and 3x2 +10x+q=0. have both roots in common?

 

Solution :

 

a1=p,b1=5,c1=2

a2 = 3, b2 = 10, c2 = q

We know that

 

Post By : Rahul Kumar 08 Apr, 2020 2672 views Maths