-1
$\begingroup$

http://i.stack.imgur.com/taL3F.jpg

b - proja(b) gives a vector that is parallel to the given line, right?

can you draw a picture or something, because I am kinda lost.

1 Answers 1

0

You can find a good explanation in any calculus textbook. Use the parametric equation of a line.

Hint: When two lines are perpendicular, their dot product is zero.

Is there a value of $t$ that gives $\vec b - {\text{pro}}{{\text{j}}_{\vec a}}\vec b$?