Chapter 3, Problem 19P

The vector $\stackrel{\to }{A}$ has x, y, and z components of 8.00, 12.0, and −4.00 units, respectively. (a) Write a vector expression for $\stackrel{\to }{A}$ in unit-vector notation. (b) Obtain a unit-vector expression for a vector $\stackrel{\to }{B}$ one-fourth the length of $\stackrel{\to }{A}$ pointing in the same direction as $\stackrel{\to }{A}$. (c) Obtain a unit-vector expression for a vector $\stackrel{\to }{C}$ three times the length of $\stackrel{\to }{A}$ pointing in the direction opposite the direction of $\stackrel{\to }{A}$.