Sin(Пи-A)=0.6                    A принадлежит (90:180)найтиtg2A

[latex]sin(pi - alpha )=sin alpha =0,6\\cos alpha =-sqrt{1-sin^2 alpha }=-sqrt{1-0,36}=-0,8; ,;; t.k.; 90 extless alpha extless 180\\tg alpha =-frac{0,6}{0,8}=-0,75=-frac{3}{4} \\tg2 alpha =frac{2tg alpha }{1-tg^2 alpha }=frac{-frac{6}{4}}{1-frac{9}{16}}=frac{-6cdot 16}{7cdot 4}=frac{-24}{7}=-3,42857[/latex]

[latex]sin( pi - alpha )=0.6 \ sin( pi - alpha )=sin alpha \ sina=0.6 \ \ cosa=- sqrt{1-sin ^{2} alpha } =- sqrt{1-0.6 ^{2} } =- sqrt{1-0.36} = \ =- sqrt{0.64} =-0.8 \ \ \ tg alpha = frac{sin alpha }{cos alpha } = frac{0.6}{-0.8} =- frac{0.6}{0.8} =- frac{6}{8} =- frac{3}{4} \ [/latex][latex] \ tg2 alpha = frac{2tg alpha }{1-tg ^{2} alpha } = frac{2*(- frac{3}{4}) }{1-( -frac{3}{4} ) ^{2} } = frac{- frac{3}{2} }{1- frac{9}{16} } =- frac{ frac{3}{2} }{ frac{16}{16}- frac{9}{16} } = \ =- frac{ frac{3}{2} }{ frac{7}{16} } =- frac{3}{2} / frac{7}{16} =- frac{3*16}{2*7} =- frac{3*8}{7} =- frac{24}{7} =- 3frac{3}{7} [/latex]