I haveQuote:

Consider two vectors byA = 2 i - 2 jandB = - i - 6 j.

1) What is the direction ofA + B? (from the +x axis)

A + B= 1i- 8j, and |A + B| = 8.06,

what i need to do to get the direction?

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- Sep 2nd 2008, 02:37 PMvietVectorsQuote:

Consider two vectors by**A = 2 i - 2 j**and**B = - i - 6 j**.

1) What is the direction of**A + B**? (from the +x axis)

**A + B**= 1**i**- 8**j**, and |**A + B**| = 8.06,

what i need to do to get the direction? - Sep 2nd 2008, 02:40 PMChris L T521
The angle is determined by $\displaystyle \vartheta=\tan^{-1}\left(\frac{v_y}{v_x}\right)$, where $\displaystyle v_x~and~v_y$ are the components of a vector $\displaystyle \vec{v}$

So, in our case, $\displaystyle \vec{A}+\vec{B}$ (which I will denote as $\displaystyle \vec{V}$) is $\displaystyle \vec{i}-8\vec{j}$

Thus, $\displaystyle \vartheta=\tan^{-1}\left(\frac{-8}{1}\right)\approx\dots$

I hope this helps! (Sun)

--Chris - Sep 2nd 2008, 02:51 PMviet
easier than what i expected. tyvm Chris.