Processing Math: Done
Lösung 4.2:3f
Aus Online Mathematik Brückenkurs 1
(Unterschied zwischen Versionen)
K (Lösning 4.2:3f moved to Solution 4.2:3f: Robot: moved page) |
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- | + | The point on the unit circle which corresponds to the angle | |
- | < | + | <math>-{\pi }/{6}\;</math> |
- | + | lies in the fourth quadrant. | |
- | + | ||
- | + | ||
- | + | ||
[[Image:4_2_3_f1.gif]] | [[Image:4_2_3_f1.gif]] | ||
+ | |||
+ | As usual, | ||
+ | <math>\cos \left( -{\pi }/{6}\; \right)</math> | ||
+ | gives the | ||
+ | <math>x</math> | ||
+ | -coordinate of the point of intersection between the angle's line and the unit circle. In order to determine this point, we introduce an auxiliary triangle in the fourth quadrant. | ||
[[Image:4_2_3_f2.gif]] | [[Image:4_2_3_f2.gif]] | ||
+ | |||
+ | We can determine the edges in this triangle by simple trigonometry and then translate these over to the point's coordinates. | ||
[[Image:4_2_3_f3.gif]] | [[Image:4_2_3_f3.gif]] | ||
+ | |||
+ | The coordinates of the point of intersection are | ||
+ | <math>\left( \frac{\sqrt{3}}{2} \right.,\left. -\frac{1}{2} \right)</math> | ||
+ | and in particular | ||
+ | <math>\cos \left( -{\pi }/{6}\; \right)=\frac{\sqrt{3}}{2}</math>. |
Version vom 12:35, 28. Sep. 2008
The point on the unit circle which corresponds to the angle
6
As usual,
−
6
We can determine the edges in this triangle by simple trigonometry and then translate these over to the point's coordinates.
The coordinates of the point of intersection are
2
3
−21
−
6
=2
3