Demuestra las siguientes igualdades:
1. 1/sec 30° csc 120 ° = 3/4
2. sen 75° cos 45° sen 225° cos 75° = -2 - 3
3. cos 35° sen 10° + cos 10° sen 35° cos 20° cos 10° sen 20° sen 10° = 3/4
4. tan 6/tan 5π/12 + tan π/12 tan 5/12 = 2 + 3
5. sen x cos x + cos 3x sen x = 1/2 sen 4x
6. cos x + 6 sen x/6 = 1/2 sen 2x
7. sen^2(3/2x) cos^2x - 2cos^2(3/2x) sen^2(2x) = sec x
8. cos x[cos 2x - 2sen^2x] = cos 3x
9. tan x + 3 tan 3x = 2 cos 2x +1/2 cos 2x - 1
10. sen(10° + x) cos (20° - x) + cos(80° - x)sen(70° + x) = sen(2x - 10°)
11. sen^2(9 + x) cos^2(1/18 + x) - sen^2(5/18x) cos^2(4/9x) = 1/2
12. sen^2x csc^2(2x) senx csc 3/2 + 2x = sen 3x
13. cos 2x + 2[sen x cos y + cos x sen y] sen(x - y) = cos 2y
14. sen^2x · sen^3/2x · cos x = cos^3x