SOLUTION: Find the angle between the given vectors to the nearest tenth of a degree. u = <8, 7>, v = <9, 7>

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Question 1089497: Find the angle between the given vectors to the nearest tenth of a degree.
u = <8, 7>, v = <9, 7>
Found 2 solutions by MathLover1, ikleyn:
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
u+= <8, 7>,+v = <9, 7>
u%2Av+=abs%28abs%28u%29%29+abs%28abs%28v%29%29+cos%28theta%29 ............abs%28abs%28u%29%29 and abs%28abs%28v%29%29 are the length of vectors u and v
u%2Av = <8, 7>*<9, 7>=>8%2A7%2B9%2A7=56%2B63=119

abs%28abs%28u%29%29+=+sqrt%288%5E2%2B7%5E2%29=sqrt%28113%29
abs%28abs%28v%29%29=sqrt%289%5E2%2B7%5E2%29=sqrt%28130%29
u%2Av+=+abs%28abs%28u%29%29%2A+abs%28abs%28v%29%29+cos%28theta%29
119+=+sqrt%28113%29+%2Asqrt%28130%29+cos%28theta%29
cos%28theta%29+=+119%2F%28sqrt%28113%29+%2Asqrt%28130%29%29
cos%28theta%29+=+119%2Fsqrt%2814690%29
theta+=+cos%5E-1%28119%2Fsqrt%2814690%29%29+
theta+=10.9°

Answer by ikleyn(52812) About Me  (Show Source):
You can put this solution on YOUR website!
.
On dot-product, see the lessons
    - Dot-product of vectors in a coordinate plane and the angle between two vectors
    - Perpendicular vectors in a coordinate plane
    - Solved problems on Dot-product of vectors and the angle between two vectors
in this site.


Also,  you have this free of charge online textbook in ALGEBRA-II in this site
    ALGEBRA-II - YOUR ONLINE TEXTBOOK.

The referred lessons are the part of this online textbook under the topic  "Dot-product for vectors in a coordinate plane".