Processing Math: Done
To print higher-resolution math symbols, click the
Hi-Res Fonts for Printing button on the jsMath control panel.

jsMath

Solution 4.2:5a

From Förberedande kurs i matematik 1

Revision as of 11:01, 9 October 2008 by Tek (Talk | contribs)
(diff) ←Older revision | Current revision (diff) | Newer revision→ (diff)
Jump to: navigation, search

Because 135=90+45, 135 is an angle in the second quadrant which makes an angle of 45 with the positive y-axis.

We can determine the point on the unit circle which corresponds to 135 by introducing an auxiliary triangle and calculating its edges using trigonometry.

oppositeadjacent=1sin45=12=1cos45=12

The coordinates of the point are (1212)  and this shows that cos135=12 .