Task/26548546
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29.
26sin750° =26sin(2*360° +30°) =26sin30° =2*1/2 =1.
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30.
-17tg765° = -17tg(4*180°+45°) = -17tg45° =-17*1 = -17.
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31.
cosx = -√(1 -sin²x ) = -√(1 -( -0,8)² ) = -√(1 -0,64 ) = -√0,36 = - 0,6.
* * * 180° < x < 270° (третий четверт) , cosx <0 * * *