Show All Work Please

1) solve: cos2x-cos6x=0

and

2) The number of hours daylight in Detroit on day 't' ( with t = 0 on January 1st) of a non-leap year is given by:

d(t)=3sin[(2π/365)(t-80)]+12

a) What days have exactly 11 hrs. of daylight

b)What day has a maximum amount of daylight

if you thought those were easy try

Solve: X (to the 3/8) - (square root of negative one)(square root of 3)=3