Year 12s: what will be the first way you research your future options? >>

Vector Scalar Product?

A, B, C are the points (1,2,-7), (3,0,5) and (2,-1,5) respectively. Find angle BAC to the nearest 0.1.
Hi, I've answered many vector Scalar questions but I can't figure out what I have to do here. Please help. Thanks.

Reply 1

james22

You should know a forumla involving the angle, the dot product and the distance.

Reply 2

pkozman

It'll help if you draw a triangle first for the visual

Then draw two vectors that are tail to tail with angle BAC between them

Then use a formula isolated for the angle

Sorry I'm on my phone can't type much