Processing Math: Done
Solution 4.2:4a
From Förberedande kurs i matematik 1
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| - | {{ | + | It can be a little difficult to draw the angle <math>11\pi/6</math> straight onto a unit circle, but if we rewrite <math>11\pi/6</math> as |
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| - | {{ | + | {{Displayed math||<math>\frac{11\pi}{6} = \frac{6\pi+3\pi+2\pi}{6} = \pi + \frac{\pi}{2} + \frac{\pi}{3}</math>}} |
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| + | we see that we have an angle that lies in the fourth quadrant, as in the figure below to the left. | ||
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| + | We also note that this angle corresponds to exactly the same point on the unit circle as the angle <math>-\pi/6</math>, and because we calculated <math>\cos (-\pi/6)</math> in exercise 4.2:3f, we have that | ||
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| + | {{Displayed math||<math>\cos\frac{11\pi}{6} = \cos\Bigl(-\frac{\pi}{6}\Bigr) = \frac{\sqrt{3}}{2}\,\textrm{.}</math>}} | ||
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| + | [[Image:4_2_4_a.gif|center]] | ||
Current revision
It can be a little difficult to draw the angle 
66
| =66+3+2=+2+3 |
we see that we have an angle that lies in the fourth quadrant, as in the figure below to the left.
We also note that this angle corresponds to exactly the same point on the unit circle as the angle 66)
=cos −6 =2 3. |
