for the derivative is

following that logic, derivative of is and

for the derivative is given as

so for the derivative is and the double derivative is

then

find the inflection points by setting F''(x) to zero and solving for x.

check where it is positive and where it is negative i.e. find concavity

you should end up with one concave down which means there is only one maximum.

how many concave up you end up isn't important here.