Answer: Choice B
[tex]\frac{1}{\sqrt{65}}<-4, 7>[/tex]
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Explanation:
Consider a right triangle with legs a = 4 and b = 7. Through the pythagorean theorem, the hypotenuse is
c = sqrt(a^2+b^2) = sqrt(4^2+7^2) = sqrt(65)
This represents the length of the vector <-4,7>
Dividing each component by the length will normalize the vector. This is the same as multiplying by [tex]\frac{1}{\sqrt{65}}[/tex] which is what choice B shows. The phrasing "normalize the vector" means "make the vector to be of length 1". A common application of normalizing vectors will come up in computer graphics.
The original vector and the vector mentioned in choice B point in the same direction. The only thing that has changed is the length from sqrt(65) to 1.
