- #1
tiffanysnsd
- 23
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So I have constructed this vector for a physics problem:
http://img23.imageshack.us/img23/1753/vectorx.jpg
Why is it when I take the tangent of the labelled angle, I get an angle of 77*, which is the complementary pair for the correct angle (which is 13*).
I can rationalize this by adding 90* to the calculated angle of 77*, the sum for which is 167*. 180*-167* = 13*, so I get the correct answer by accounting for the quadrant the vector is located in. But in my (admittedly limited) experience with vectors, I have never had to adjust the calculated angles for the quadrant (on a cartesian plane) where the vector is located; the trigonometric ratio between the two sides has always given the correct angle.
http://img23.imageshack.us/img23/1753/vectorx.jpg
Why is it when I take the tangent of the labelled angle, I get an angle of 77*, which is the complementary pair for the correct angle (which is 13*).
I can rationalize this by adding 90* to the calculated angle of 77*, the sum for which is 167*. 180*-167* = 13*, so I get the correct answer by accounting for the quadrant the vector is located in. But in my (admittedly limited) experience with vectors, I have never had to adjust the calculated angles for the quadrant (on a cartesian plane) where the vector is located; the trigonometric ratio between the two sides has always given the correct angle.
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