Processing Math: Done
Solution 4.4:8b
From Förberedande kurs i matematik 1
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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). |
Revision as of 13:39, 1 October 2008
Suppose that
=0
3
3
This equation has the solutions
3+n
If, on the other hand,
1
Thus, the equation has the solutions
3+n