Small angle approximation

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Smaa angle approximation is a wey o estimatin angles in radians, whaur the angle is smaa (less than 3 or 4 degrees).

Whan x is smaa, an in radians, the follaein formulae are true:

\sin x \simeq x

\cos x \simeq 1 - \frac{x^2}{2}

\tan x \simeq x