Задача 8517 4sin(17П/6)*cos(23П/3)...

VyacheslavMaslakov

13.04.2016

4sin(17П/6)*cos(23П/3)

Sova

13.04.2016

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По формулам приведения

sin(17π/6)=sin(18π-π)/6=sin(3π-(π/6))=sin π/6=1/2;
cos(23π/3)=cos(24π-π)/3=cos(8π-(π/3))=cos π/3=1/2;

4 · sin(17π/6)·cos(23π/3)=1