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Find the angle θ between vectors r and s, where |r| = 16, |s| = 9, and r · s = 125.

User Psychotik
by
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2 Answers

19 votes
19 votes

Answer: C. θ = 29.77°

Explanation:

Find the angle θ between vectors r and s, where |r| = 16, |s| = 9, and r · s = 125.-example-1
User Matthew Holmes
by
2.9k points
22 votes
22 votes

Explanation:

Hi there!

From the question;

|r| = 16

|s| = 9

And r.s = 125

We know that;


r.s = |r| . |s| * \cos(θ)

Now, Keep the values from given;

125 = 16*9*(cosθ)

cos θ= 125/144

cos θ = 0.86

θ = cos'(0.86)

θ = 30.68°

Therefore, the angle of θ made by vector r and s is 30.68°.

Hope it helps!

User Lye Heng Foo
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3.0k points