Sine and cosine function

The functions  $ f(x) = \sin x$ and $ f(x) = \cos x$ are respectively called a sine and cosine function. The domain of both sine and cosine functions is $ {D = (-\infty, \infty)}$, and their range is $ R = [-1,1]$.

  (S) $ y = \sin x$
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  (C) $ y = \cos x$

Odd and even. The sine function is odd, and the cosine function is even. That is,

$\displaystyle \sin(-x) = - \sin x$    and $\displaystyle \quad
\cos(-x) = \cos x .

Department of Mathematics
Last modified: 2005-09-29