What is the unit vector of this vector v = -2i + 5j?

1 Answer
Jul 15, 2016

color(blue)(vec(u)=-2/sqrt(29)i+5/sqrt(29)j) is a unit vector with the same direction as vec(v)=-2+5j

Explanation:

The unit vector, vec(u) corresponding to a given vector vec(v) can be calculated by dividing the terms of vec(v) by the magnitude (length) of vec(v)

color(white)("XXX")vec(u)=vec(v)/abs(vec(v))

abs(vec(v)) is calculated using the Pythagorean Theorem.
In this case with vec(v)=-2i+5j
color(white)("XXX")abs(vec(v))=sqrt((-2)^2+5^2)=sqrt(29)