If |u+v|=|u-v|, then u*v must be equal to:  Answers.
A) 2
B) 0
C) -3
D) 3
E) -2
Solution 1: Distance perspective   |u-v| = |u+s| ==&gt; The distance of u and v is equal to the distance of u and -v.   &lt;=======(-v)=======0=======(v)======&gt;   Only 0 is the value that has a distance equal to v and -v.   Solution 2:   |u-v| = |u+v| (square both)   u^2 -2uv + v^2 = u^2 + 2uv + v^2   4uv = 0   uv = 0   Answer: 0
<result>B</result>
If |u+v|=|u-v|, then u*v must be equal to: