Consider f(x)={cosx,(2π−x)2,0≤x<2π2π≤x<π such that f is periodic with period π , then
a. the range of f is [0,4π2]
b. f is continuous for all real x , but not differentiable for some real x
c. f is continuous for all real x
d. the area bounded by y=f(x) and the X -axis from x=−nπ to x=nπ is 2n(1+24π2) for a given n∈N