Sin^2(3pi/2-y)+sin^2(3pi+y)+2tg(5pi/2-y)×tg (3pi+y)
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Решение
Вычислить Sin²(3π/2-y)+sin²(3π+y)+2tg(5π/2-y)*tg (3π+y) .
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Применяя формулы приведения ,получаем :
Sin²(3π/2-y)+sin²(3π+y)+2tg(5π/2-y)*tg (3π+y)= (cos²y +sin²y)+ 2ctqy*tqy =1 +2*`1 =3.
ответ : 3.
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sin (3π/2-y)) = -cosy
sin(3π +y ) =sin( (2π+(π +y ) )=sin(π +y ) = -siny
tg(5π/2-y) =tg((2π +(π/2-y) ) =tq(π/2-y) =ctqy
tq(3π +y ) =tq( (2π+(π +y ) ) =tq(π +y ) =tqy