Предмет: Алгебра, автор: JuliaIvanovaV

12-25 cos^2(п-a)tg^2(2п-a) если sina=1/2корня из5

Ответы

Автор ответа: serebrakov2016
0
12+25cos^2 a(формула приведения) * (-tg^2 a)(формула пивед.) = 
12+25cos^2a*(-sin^2a/cos^2a)=12-25sin^2a=12-25*(1/2*)^2=
12-25*1/4*5=12-31,25=-19,25
Автор ответа: Universalka
0
Sina = 1/2√5, а не 1/2
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