sin(90+x) | cosx | sin(180-x) | sinx | sin(180+x) | -sinx | ||
cos(90+x) | -sinx | cos(180-x) | -cosx | cos(180+x) | -cosx | ||
tan(90+x) | -cotx | tan(180-x) | -tanx | tan(180+x) | tanx |
For angle>180 degree, use the formulae- sin(180+A ) = - sinA cos (180+A) = - cosA tan(180+A )= tanA cos of any angle lags behind sin graph by 90 degree Exa- cos 90 has same value as sin (90+90)=sin 180 cos of an angle lags behind the sine by phase difference of 90 degree. i.e sin 90= cos(90-90)=cos 0