f(x) = 2sin2(2x)Therefore, using the chain rule: f'(x)=2 x 2cos(2x) x 2sin(2x)(The 2 at the front arises from the constant 2, at the start of f(x), the 2cos(2x) comes from differentiating sin
If wavelength = 0.1nm, we know (as E=hc/λ), the energy provided by each photon, E= 1.99x1015 J .Therefore, if they hit the panel at a rate of 2.51x1015