2^x=X^2
Ln2^x=Lnx^2 , x>0
xLn2=2lnx
Lnx/x=Ln2/2
fx=lnx/x , x>0
f'x=1-lnx/x^2 , x>0
f'x>0 for x<e
that means f(x)for x belongs to (o,e]
and f'(x)for x belongs to [e,+~)
As a result f has to possible solution one in (0,e] and the other in [e,+~)
f have the possible solution of x=2 and x=4 As a result 2^x-X^2 has to solutions x=2 and x=4