# Vector

• Apr 29th 2008, 02:07 AM
ah-bee
Vector
If
u, v is a member ofR^n, find u · v given that |u + v| = 1 and |u v| = 5.

• Apr 29th 2008, 02:13 AM
Isomorphism
Quote:

Originally Posted by ah-bee
If
u, v is a member ofR^n, find u · v given that |u + v| = 1 and |u v| = 5.

HINT: $|u+v|^2 - |u-v|^2 = 4(u.v)$