Given that A+B+C=0. Find the magnitudes of A and B

Question

Given that A+B+C=0. Find the magnitudes of A and B

Answer 1

Hi Samo,

The magnitude of A and B are the dot product of the vector and itself.

A+B+C=0

A = -B - C

B = -A - C

|A| = A² =  A•A = B² + C² +2B•C 

|B| = B² = B•B  = A² + C² +2A•C