In this site,The frequency of a trigonometric function is defined as the number of cycles it completes in a given interval.
The formula is : frequency=1/period
The period of a sine function is $2\pi$ [Is it true for all sine function,i.e., basic and general sine function?].
So by formula : frequency=1/$2\pi$.
But, the sine curve completes 1 cycles in the interval $0$ to $2\pi$. So its frequency is $1$.
Why does it conflict with formula?
Where am i doing mistake?
The problem seems to be the first line, where you state that the frequency is the number of cycles in a given interval. Frequency would better be defined as the number of oscillations per unit time. If the period is $T=2\pi$, than the frequency becomes $\nu=\frac{1}{T}$.
Choosing the frequency as the number of oscillations in a given interval is not a good definition, because the frequency would then depend on your choice of the interval and one function could have multiple frequencies.