My method is a bit different .
eax2 - e2ax + ea - 1 = 0 lies between 1 and 2.
Let ea = b
and let y = eax2 - e2ax + ea - 1 = 0
Therefore ,
y = bx2 - b2x + b - 1 = 0.
We know that 1<y<2
So we can write it as
(y-1)(y-2) < 0
(bx2 - b2x + b - 2) (bx2 - b2x + b - 3) < 0
So we now have two quadratics Q1 and Q2.
No we will have two cases.
Q1 < 0 and Q2> 0 : and : Q1 > 0 and Q2 < 0
Get the solution for both and take thier intersection to get the answer,
Hope it helped you.
Cheers !!!!!!!!!!!!!!!!!!!