Спростити: 1)Sin x cos y + cos x sin y = 2) tg 47° - tg 17°/ 1+tg 47° * tg 17° = 3) cos...

Question

Спростити:
1)Sin x cos y + cos x sin y =
2) tg 47° - tg 17°/ 1+tg 47° * tg 17° =
3) cos 2α / cos α – sin α =
4)tg 2α / tg 4α – tg 2α =

Comments

the second question ×tg17 where exactly

Answer 1

Четвёртое не знаю, извини

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