Grade 12th passIntegral Calculus
Let f:[1/2,1] R be a positive,non constant function and differentiable function such that
f’(x)(first deriative)<2f(x) and f(1/2)=1
Then the value of 
a=1/2,b=1
a=1/2,b=1 lies in the interval
A (2e-1,2e)
B (e-1,2e-1)
C (e-1/2,e-1)
D (0,e-1/2)
Multiple correct
Please answer quickly
