Question

решите пример по алгебре 9.31 (б)

Answer 1

$sin alpha = sqrt{1-cos^2 alpha } = sqrt{1-0.04 } = sqrt{0.96 } \ sin beta = -sqrt{1-cos^2 beta } =-sqrt{1-0.01 } = -sqrt{0.99 } \ sin( alpha - beta )=sin alpha cos beta -cos alpha sin beta = \ -0.1sqrt{0.96 } -(-0.2)( -sqrt{0.99 } )=-0.4sqrt{0.06 } -1.8sqrt{0.11 }$