Найдите 1+5sin(2a)-3cos^{-1} [/tex](2a) , если tga=-2. Created by ksmrksmr. algebra-ru

tex](2a) , если tga=-2...

ksmrksmr @ksmrksmr

July 2022 1 13 Report

Найдите 1+5sin(2a)-3cos^{-1} [/tex](2a) , если tga=-2

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sedinalana

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Cos²a=1:(1+tg²a)=1:(1+4)=1/5
cosa=1/√5
sina=-√(1-cos²a)=-√(1-1/5)=-2/√5
sin2a=2sinacosa=2*(-2/√5)*1/√5=-4/5
cos2a=2cos²a-1=2*1/5-1=2/5-1=-3/5
1+5sin2a-3/cos2a=1-5*4/5-3:(-3/5)=1-4+5=2

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