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5 votes
Find the magnitude and direction angle of the vector v. (Round the direction angle to one decimal place.)

v = −10i + 16j

magnitude= sqrt356
I just need the direction angle

User Deidre
by
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1 Answer

6 votes

Answer:

122°

Explanation:

The direction angle can be calculated as shown:


\displaystyle \theta=\tan^(-1)\biggr((y)/(x)\biggr)=\tan^(-1)\biggr((16)/(-10)\biggr)\approx-58^\circ

Since the vector is in Quadrant II, then we find that
180^\circ-58^\circ=122^\circ is the true direction angle.

User Themazz
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8.3k points