The correct option is C f(x) is invertible in [0,π4]
∵1≤|sin2x|+|cos2x|≤√2So, [ |sin2x|+|cos2x| ]=1f(x)=ln (1)=0
⇒ it is periodic but fundamental period is not defined.
Also, (R−∩Range of f(x)) is a null set
f(x) is many one and into fucntion.
Hence, f(x) is not invertible.