Showing posts with label practice problems. Show all posts
Showing posts with label practice problems. Show all posts

Tuesday, December 4, 2012

vectors and angles




Here are some two dimensional vectors. Find the difference between the vectors, both U-V and V-U, the dot products U·U, V·V, U·V, length of the vectors and the cosine of the angle between them, which is given by the formula in the picture above.

Example

U = <4 3> and V = <0 5>

U·U =  25

V·V =  25

U·V = 15

||U|| = sqrt(25) = 5

||V|| = sqrt(25) = 5

costheta = 15/25 = 3/5

theta ~= 53.1301°

Practice.

U = <4 3> and V = <3 -4>

U·U = ______

V·V =  ______

U·V =______

||U|| = ______

||V|| = ________

costheta = ______

theta = _______

U-V = _______

||U-V|| = _________

cosine of angle between U and U-V = ________


angle to nearest thousandth of a degree = _______


V-U = _______

||V-U|| = _________

cosine of angle between V and V-U = ________


angle to nearest thousandth of a degree = _______



Answers in the comments.