Question

If both roots of the equation 4x² - 12ax + (9a² - 4a + 8) = 0 exceed 3, then the set of exhaustive values of a is​

Answer 1

Now, here k=3 .

From (1), we have a≥1

From (2), we have a>1

From (3), we have (9a−11)(a−1)>0 ie a<1or a>911. 

After taking the common region satisfied by all the above inequalities we get our answer as 

a>911.

Answer 2

1. add 3 to 0 and multiply LHS by 3
2. then solve it