What is the value of 2sin68°/cos22° - 2cot15°/(5tan75°) - 3tan20°tan40°tan45°tan50°tan70°/5?

2sin68°/cos22° = 2 (sin68°=cos22°). 2cot15°/(5tan75°) = 2/5 (cot15°=tan75°). tan20°tan70°=1, tan40°tan50°=1, tan45°=1, so third term = 3/5. Total = 2 - 2/5 - 3/5 = 1.