Lösung 4.4:8b
Aus Online Mathematik Brückenkurs 1
(Unterschied zwischen Versionen)
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| - | {{ | + | Suppose that |
| - | < | + | <math>\text{cos }x\ne 0</math> |
| - | {{ | + | , so that we can divide both sides by |
| + | <math>\text{cos }x</math> | ||
| + | to obtain | ||
| + | |||
| + | |||
| + | <math>\frac{\sin x}{\cos x}=\sqrt{3}</math> | ||
| + | i.e. | ||
| + | <math>\tan x=\sqrt{3}</math> | ||
| + | |||
| + | |||
| + | This equation has the solutions | ||
| + | <math>x=\frac{\pi }{3}+n\pi </math> | ||
| + | for all integers | ||
| + | <math>n</math>. | ||
| + | |||
| + | If, on the other hand, | ||
| + | <math>\text{cos }x=0</math>, so | ||
| + | <math>\text{sin }x\text{ }=\pm \text{1}</math> | ||
| + | ( draw a unit circle) and the equation cannot have such a solution. | ||
| + | |||
| + | Thus, the equation has the solutions | ||
| + | |||
| + | |||
| + | <math>x=\frac{\pi }{3}+n\pi </math> | ||
| + | ( | ||
| + | <math>n</math> | ||
| + | an arbitrary integer). | ||
Version vom 13:39, 1. Okt. 2008
Suppose that \displaystyle \text{cos }x\ne 0 , so that we can divide both sides by \displaystyle \text{cos }x to obtain
\displaystyle \frac{\sin x}{\cos x}=\sqrt{3}
i.e.
\displaystyle \tan x=\sqrt{3}
This equation has the solutions
\displaystyle x=\frac{\pi }{3}+n\pi
for all integers
\displaystyle n.
If, on the other hand, \displaystyle \text{cos }x=0, so \displaystyle \text{sin }x\text{ }=\pm \text{1} ( draw a unit circle) and the equation cannot have such a solution.
Thus, the equation has the solutions
\displaystyle x=\frac{\pi }{3}+n\pi
(
\displaystyle n
an arbitrary integer).
