posted by .

Use the law of cosines to find the angle Q between the given vectors.

v = 3i + j w = 2i - j

v•w = |v| |w|cos Ø

v•w = 6 - 1 = 5
5 = √10√5cosØ
cosØ = 5/√50
Ø = 45°

## Similar Questions

1. ### Physics

Two dogs pull horizontally on ropes attached to a post; the angle between the ropes is 65.0. Dog exerts a force of 256 and dog exerts a force of 344 . A) Find the magnitude of the resultant force. B) Find the angle the resultant force …
2. ### Pre-Cal

Use the law of cosines to find the angle of Q between the given vectors. v=3i + j w=2i - j
3. ### Math

Use the law of cosines to find the angle Q between the given vectors. v = 3i + j w = 2i - j
4. ### Pre Cal/Vectors

Can someone show the steps involved in figuring out this type of problem?
5. ### Pre-Calc Helppp!!!

Find the indicated angle è. (Use either the Law of Sines or the Law of Cosines, as appropriate. Assume a = 110 and c = 136 (angle B=38) Round your answer to two decimal places.)

Find the indicated angle è. (Use either the Law of Sines or the Law of Cosines, as appropriate. Assume a = 95 and c = 137(angle B=38). Round your answer to two decimal places.)
7. ### Trigonometry/Geometry - Law of sines and cosines

In most geometry courses, we learn that there's no such thing as "SSA Congruence". That is, if we have triangles ABC and DEF such that AB = DE, BC = EF, and angle A = angle D, then we cannot deduce that ABC and DEF are congruent. However, …
8. ### Pre calculus

Why is it dangerous to use the law of sines to find an angle but is not dangerous to use the law of cosines?
9. ### Trig

I need help with my vectors unit. I'm really confused about how to set them up. Please help. a.) Given u=2i-5j and v=-i+3j, determine -6u-3v?
10. ### pre cal

Find the angle between the vectors u and v if u=i+4j and v=−i+2j.

More Similar Questions