Vectors - determining ##\angle abc##

[angela107]

Homework Statement

can someone see if my work is correct?

Relevant Equations

n/a

 

[member 587159]

I think you made an error with calculating the vector $\vec{BC}=[-4,0,0]$. I think you missed the minus sign here. You also want to consider $\vec{BA}$ instead of $\vec{AB}$, so your solution checks out because two negatives cancel each other out.

Perhaps I'm misunderstanding your convention but I use $\vec{AB}= \vec{B}- \vec{A}$.