From Förberedande kurs i matematik 1

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-	{{NAVCONTENT_START}}	+	The right-hand side of the equation is a constant, so the equation is in fact a normal trigonometric equation of the type <math>\cos x = a\,</math>.
-	<center> [[Bild:4_4_3a.gif]] </center>	+
-	{{NAVCONTENT_STOP}}	+
-	[[Bild:4_4_3_a.gif|center]]	+	In this case, we can see directly that one solution is <math>x = \pi/6\,</math>. Using the unit circle, it follows that <math>x = 2\pi - \pi/6 = 11\pi/6\,</math> is the only other solution between <math>0</math> and <math>2\pi\,</math>.
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		+	[[Image:4_4_3_a.gif|center]]
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		+	We obtain all solutions to the equation if we add multiples of <math>2\pi</math> to the two solutions above,
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		+	{{Displayed math||<math>x = \frac{\pi}{6} + 2n\pi\qquad\text{and}\qquad x = \frac{11\pi}{6} + 2n\pi\,,</math>}}
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		+	where ''n'' is an arbitrary integer.

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Current revision

The right-hand side of the equation is a constant, so the equation is in fact a normal trigonometric equation of the type \displaystyle \cos x = a\,.

In this case, we can see directly that one solution is \displaystyle x = \pi/6\,. Using the unit circle, it follows that \displaystyle x = 2\pi - \pi/6 = 11\pi/6\, is the only other solution between \displaystyle 0 and \displaystyle 2\pi\,.

We obtain all solutions to the equation if we add multiples of \displaystyle 2\pi to the two solutions above,

\displaystyle x = \frac{\pi}{6} + 2n\pi\qquad\text{and}\qquad x = \frac{11\pi}{6} + 2n\pi\,,

where n is an arbitrary integer.