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Active Calculus - Multivariable

Activity 9.3.5.
In Figure 9.3.8, you can see illustrations of splitting \(\vu\) into two parts: \(\vw_1\text{,}\) which is parallel to \(\vv\text{,}\) and \(\vw_2\text{,}\) which is orthogonal to \(\vv\text{.}\) Use this figure for reference as you do the following.
(a)
We know from the previous subsection that there is a third configuration of vectors, which occurs when \(\vu\) and \(\vv\) are orthogonal. Suppose that \(\vu\) and \(\vv\) are nonzero orthogonal vectors. What would \(\vw_1\) and \(\vw_2\) be in this case?
(b)
We want to switch the roles of \(\vu\) and \(\vv\) for the examples in the previous parts. Specifically, for these configuration of vectors, we want to split \(\vv\) into parts that are parallel to \(\vu\text{,}\) which we will call \(\vz_1\text{,}\) and orthogonal to \(\vu\text{,}\) which we will call \(\vz_2\text{.}\) On Figure 9.3.9, draw \(\vz_1\) and \(\vz_2\) for each configuration.
described in detail following the image
Vector \(\vv\) points horizontally with \(\vu\) above it making an acute angle \(\theta\text{.}\)
described in detail following the image
Vector \(\vv\) points horizontally with \(\vu\) above it making an obtuse angle \(\theta\text{.}\)
Figure 9.3.9. A plot of \(\vu\) and \(\vv\)
Based on your drawing, is it the case that \(\vw_1 = \vz_1\text{?}\) What about \(\vw_2\) and \(\vz_2\text{?}\)
Hint.
You may find it useful to rotate your paper so that \(\vu\) appears horizontally.