The effective value of current `i=2 sin (100 pi t) +2 cos (100pi t +30^@)` is:

Explanation

The equation can be written as `i=2sin 100 pit+2 sin (100 pi t+120^(@))`
so phase difference `phi=120^(@)` `I_(m))_(res)=sqrt(A_(1)^(2)+A_(2)^(2)+2A_(1)A_(2)cos phi)`
`=sqrt(4+4+2xx2xx2((-1)/(2)))=2 "so effective value or rms value"=2//sqrt2=sqrt2A`