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What is the angle theta between vectors

  • #1

Homework Statement


What is the angle theta between vectors vec A and vec B if vec A = 4 -3 and
vec B = -2 + 5?


Homework Equations


arccos((a dot b)/(|a||b|))


The Attempt at a Solution



4*-2+-3*5=-23
sqrt(4^2+-3^2)*sqrt(-2^2+5^2)=10.39

arc
not sure what i am doing wrong but thats the equation i found online and i keep getting undefined when i plug it into my calculator
 
Last edited:

Answers and Replies

  • #2
Doc Al
Mentor
44,904
1,169
Show what you plugged in.
 
  • #3
edited the question, but sorry i realized my error, had a mistake in the magnitudes, got the problem right
 

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