Question

sin 63 cos 33 - sin 33 cos 63
cos 71 cos 26+ sin 71 sin 26
cos 18 cos 12 - sin 18 sin 12
tg73-tg13
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1-tg73 tg13​

Answer 1

Ответ:

1)sin(66-33)=sin30=1/2

2)cos(71-26)=cos45=√2/2

3)cos(18+12)=cos30=√3/2

4)1-tg73tg(90-77)=1-tg73ctg77=1-1=0