Rewrite with only sin x and cos x.

sin 2x - cos 2x

Given:
sin2x-cos2x
now by applying double angle formula
for sin2x
sin2x = 2sinx*cosx
for cos2x 
cos2x = (cosx*cosx - sinx*sinx)
now putting these above values in given equation
2sinx*cosx - (cosx*cosx - sinx*sinx)
now simplifyng 
2sinx*cosx - cosx*cosx + sinx*sinx
so the right answer is 
2sinx*cosx - cosx*cosx + sinx*sinx

c(x) = 2.00 + 0.50x

Step-by-step explanation:

Since they already charged her $2.00 leave that alone. They charge her .50 per night, x represents the number of nights she rented the movie. thus the answer is c(x) = 2.00 + 0.50x.