# Math

Find the angle Q between the two vectors.

u = 10i + 40j v = -3j+8k

cos <10,40,0> <0,-3,8> / sqrt1700 sqrt73

cos(-120/sqrt1700 sqrt73) = .9072885394

arc cos (.9072885394) = 24.86 degrees.

Is this correct?

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1. What happened to the - sign in the Cosine term? I think that changes the angle significantly.

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bobpursley
2. I am not sure what to change.

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3. cosine is negative in the second and third quadrant.

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bobpursley

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