Split Integral: Now, let's split the integral into two parts. ∫2π4π21−cos(2x)dx=21∫2π4πdx−21∫2π4πcos(2x)dx
Calculate First Integral: Calculate the first integral, which is a constant.21∫2π4πdx=21[x]2π4π=21[4π−2π]=21[2π]=π
Calculate Second Integral: Now, calculate the second integral, which involves the cosine function.21∫2π4πcos(2x)dx=21[2sin(2x)]2π4π
Plug in Limits: Plug in the limits for the second integral.21[2sin(2x)]2π4π=21[2sin(8π)−2sin(4π)]Since sin(8π)=sin(4π)=0, this part of the integral is zero.
Add Results: Add the results of the two integrals. π+0=π So, the final answer is π.