Предмет: Математика, автор: Azero9

вычислить 1/cos670 - 1/√3cos220

Ответы

Автор ответа: 2004nasta

0

Решение:
cos670=cos(720- 50)=cos50 cos220=cos(180+50)=-cos50
1/ cos50+1/sqrt(3)cos50=(1+sqrt(3))/cos50.

Автор ответа: Azero9

0

cos(180+50) - это cos230. А у меня дан cos220

Автор ответа: 2004nasta

0

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