- #1
formulajoe
- 177
- 0
ive got two vectors and i need to find the angle between them.
AB = -1.95i + 2.4j +.3k
AC = 2.4j+1.8k
i looked up the answer and found it to be 46.8 deg.
i used the equation (AB)(AC) cos theta = ACxABx +ACyABy + ACzABz
the dot product is 6.84. but the equation ends up like this
cos theta = (ACxABx +ACyABy + ACzABz)/(AB)(AC)
this is a dot product on top and on bottom right? i don't quite understand how this works. according to the answer, ABAC should be around 10.
AB = -1.95i + 2.4j +.3k
AC = 2.4j+1.8k
i looked up the answer and found it to be 46.8 deg.
i used the equation (AB)(AC) cos theta = ACxABx +ACyABy + ACzABz
the dot product is 6.84. but the equation ends up like this
cos theta = (ACxABx +ACyABy + ACzABz)/(AB)(AC)
this is a dot product on top and on bottom right? i don't quite understand how this works. according to the answer, ABAC should be around 10.