Vectros ` vec A ,vec B and vec C` sattsfy the equation ` vec A + vec B =vec C`, and their magitues related by the equation ` A + B =C`. How is the vector `vec A` oriented with respect to vector `vec B` ? Explain your reasoning.

Explanation

If ` theta` is the angle between ` vec A and vec B`,
the ` C= (A^(2) + vec B^@ + 2 AB cos theta) ^(1//2) = (A + B) ,
[Given ]
:. ` A^2 + B^2 + 2 AB cos theta = (A + B)^2`
`= A^2 + 2 AB + B^@`
or ` cos theta=1 or theta =0^@` .