this is for holding javascript data
Yitong Li edited untitled.tex
almost 8 years ago
Commit id: ad4c9cbac624bbf6f5c75a0053e20beac494dc33
deletions | additions
diff --git a/untitled.tex b/untitled.tex
index 9384a3e..422aff4 100644
--- a/untitled.tex
+++ b/untitled.tex
...
In the second case, when $W$ is nonzero, then consider the unit vector $U = \frac{W}{||W||}$. Then, by the result in the question, it follows that $V = (U · V)U$. Therefore:
$$V = (U · V)U = (\frac{W}{||W||}· V)·\frac{W}{||W||}= (\frac{W·V}{W^2})·W$$
As $(\frac{W·V}{W^2})$ is a constant, so
$V $V$ is a multiple of
W$. $W$.