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Hello everybody.
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In this video, i'm going to be showing you how to solve exercise 11 in chapter 13, section 4 of calculus early transcendentals.
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Now in this problem, they give us graphically two vectors, u equals 3 -00 here, and v equals 0 -50 here.
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And using this picture, they want us to identify what u -cross -v is.
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There for this video, i do want to note that i am using a color key here just to make the directions a little more clear.
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Any vector in the x direction, i will draw on red, and the y direction i will draw in blue, and in the z direction i will draw in green.
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So the first part of solving this problem is that we want to find the magnitude of this vector.
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And for this, we can use theorem 13 .3.
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This theorem tells us that the magnitude of a cross product of two vectors is equal to the product of their magnitudes times the sign of the angle that separates the two vectors.
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However, we can see here that these two vectors are completely orthogonal, and therefore sine theta is equal to one.
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And therefore, this magnitude in this case is just going to be equal to the product of each vector's magnitude...