Lösung 4.4:3a
Aus Online Mathematik Brückenkurs 1
(Unterschied zwischen Versionen)
K (Lösning 4.4:3a moved to Solution 4.4:3a: Robot: moved page) |
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- | { | + | The right-hand side of the equation is a constant, so the equation is in fact a normal trigonometric equation of the type |
- | < | + | <math>\text{cos }x=a</math>. |
- | {{ | + | |
+ | 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>\text{2}\pi </math>. | ||
[[Image:4_4_3_a.gif|center]] | [[Image:4_4_3_a.gif|center]] | ||
+ | |||
+ | We obtain all solutions to the equation if we add multiples of | ||
+ | <math>\text{2}\pi </math> | ||
+ | to the two solutions above: | ||
+ | |||
+ | |||
+ | <math>x=\frac{\pi }{6}+2n\pi </math> | ||
+ | and | ||
+ | <math>x=\frac{11\pi }{6}+2n\pi </math> | ||
+ | |||
+ | |||
+ | where | ||
+ | <math>n</math> | ||
+ | is an arbitrary integer. |
Version vom 09:37, 1. Okt. 2008
The right-hand side of the equation is a constant, so the equation is in fact a normal trigonometric equation of the type \displaystyle \text{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 \text{2}\pi .
We obtain all solutions to the equation if we add multiples of \displaystyle \text{2}\pi to the two solutions above:
\displaystyle x=\frac{\pi }{6}+2n\pi
and
\displaystyle x=\frac{11\pi }{6}+2n\pi
where
\displaystyle n
is an arbitrary integer.