Помогите, пожалуйста. Срочно 1)40√3 cosπ/6 cos5π/3 2)8√6 cosπ/4 cos5π/6 3)14√6 cosπ/6...

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Помогите, пожалуйста. Срочно
1)40√3 cosπ/6 cos5π/3
2)8√6 cosπ/4 cos5π/6
3)14√6 cosπ/6 cos3π/4
4)28/(sin(-25π/4)cos(23π/4))
5)23/(sin(-23π/6)cos(23π/3))
6)60/(sin(-32π/3)cos(35π/6))
7)54/(sin(-28π/3)cos(23π/6))
8)33√2cos(495°)


Алгебра (87 баллов) | 111 просмотров
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Решение:
1) 40√3·√3/2·(-√2/2)=20·√3·√3·(-√2/2)=10·3·(-√2)=-30√2
2) 8√6 ·√2/2 ·(-√3/2)=4√6·√2·(-√3/2)=2√6·√2·(-√3)=-2√6·2·3=-2√36=-2·6=-12
3) 14√6 ·√3/2· (-√2/2)=7√6·√3·(-√2/2)=-7√18·(√2/2)
4) 28/(sin(-25π/4)cos(23π/4))=28/(-sin(6π+π/4)cos(5π+3π/4))=28/(-√2/2)·(1+(-√2/2))=14/(-√2/)·(1-√2/2)
5)23/(sin(-23π/6)cos(23π/3))=23/(sin(-3π+5π/6)cos(7π+2π/3))=23/(-1/2)(1-1/2)=23/(-1/4)=-23/4
6)60/(sin(-32π/3)cos(35π/6))=60/(
sin(-10π +2π/3)cos(5π+5π/6))=60/(-√3/2)(1+(-√3/2))=-30√3·(1-√3/2)=-30√3+15·3=-30√3+45
7)54/(sin(-28π/3)cos(23π/6))=
54/(-sin(9π)cos(5π+3π/6))=54/(0·cos(5π+3π/6)=54/0
8)33√2cos(495°)=
33√2cos(360°+135°)=33√2cos(2π+3π/4)=33√2·(1-√2/2)=33√2-33√2·(√2/2)=33√2-33·2/2=33√2-33

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