Question

1)Вычислите
2)Упростите выражение

Answer 1

sin23°cos53° -cos23°sin53° =sin(23° -53°) =sin(-30°)  =  -sin30° = -1/2 .
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(1 -tq32°tq28°)/(tq32°+tq28°) =1/ (tq(32°+28°) =1/tq60° =1/√3 .