If , prove that and
I run out of ideas.
I tried
I tried
Does anyone know how to prove this?
That result is not true. The result should be that . For example, if a=3 and b=4 then c = 25/24, which is greater than 1, but less than a or b. Edit: HallsofIvy beat me to it!
To see why , divide the equation by (assuming that ). It becomes . Now put , so that . The condition for that quadratic to have real roots is .