1)sin(a-b)+cosasinb=sinacosb-cosasinb+cosasinb=sinacosb
2)cos^2a-sin^2a=1
3)2sinasinb+cosacosb-sinasinb=cosacosb
док-во
sin5a-sin3a/2cos4a=sina
2sinacos4a/2cos4a=sina
sina=sina (В.)
sin5a - sin3a/2cos4a=(2sin((5a-3a)/2)*cos((5a+3a)/2)) / 2cos4a = 2sin a*cos4a/2cos4a= sin a
sin5a-sin3a=2sinacos4a
(sin5a-sin3a)/2cos4a=2sinacos4a/2cos4a=sina
sin5a-sin3a\2cos4a=sina
2sin(5a-3a/2)cos(5a+3A/2)/2cos4a=sina
2sina*cos4a/2cos4a=sina
sina=sina
1)sin(a-b)+cosasinb=sinacosb-cosasinb+cosasinb=sinacosb
2)cos^2a-sin^2a=1
3)2sinasinb+cosacosb-sinasinb=cosacosb
док-во
sin5a-sin3a/2cos4a=sina
2sinacos4a/2cos4a=sina
sina=sina (В.)
sin5a - sin3a/2cos4a=(2sin((5a-3a)/2)*cos((5a+3a)/2)) / 2cos4a = 2sin a*cos4a/2cos4a= sin a
sin5a-sin3a=2sinacos4a
(sin5a-sin3a)/2cos4a=2sinacos4a/2cos4a=sina
sin5a-sin3a\2cos4a=sina
2sin(5a-3a/2)cos(5a+3A/2)/2cos4a=sina
2sina*cos4a/2cos4a=sina
sina=sina
2sin(5a-3a/2)cos(5a+3A/2)/2cos(4a) = sin(a);
2sin(a)*cos(4a)/2cos(4a) = sin(a);
sin(a) = sin(a).