The electric current in a circuit is given by I = 3 sin `omegat + 4 cos omegat.` The rms current is

Explanation

`i=3sin omega t+4 cos omega t`
`(int_(0)^(t)i^(2).dt)/(int_(0)^(t)dt)=(int_(0)^(T)(3sin omegat+4cos omegat)^(2)dt)/(T)`
`=(1)/(T)int_(0)^(T)(9sin^(2)omegat+16cos^(2)omegat+12sin 2omegat)dt`
`=(25)/(2)" "therefore i_("rms")=(5)/(sqrt2)A`