Question

проверьте справедливость равенства:
а) sin93 - cos63 = sin33
б) cos14 - sin16 = cos46

Answer 1

a)sin93-cos63=sin(33+60)-cos(33+30)=sin33cos60+cos33sin60-(cos33cos30-sin33sin30)=(sin33)/2+((cos33)√3)/2-((cos33)√3)/2+(sin33)/2=sin33
b)cos(60-46)-sin(46-30)=cos60cos46+sin60sin46-sin46cos30+cos46sin30=(cos46)/2+(cos46)/2+sin60sin46-sin60sin46=cos46