# What is the speed of an object that travels from ( 2,-5,6 )  to ( 2, -4 ,1 )  over 2 s?

Mar 27, 2016

$2.55 u n i t s / s$

#### Explanation:

First find the distance between the 2 given points by using the normal Euclidean metric in ${\mathbb{R}}^{3}$.

therefored[(2,-5,6);(2,-4,1)]=sqrt((2-2)^2+(-5-(-4))^2+(6-1)^2)

$= \sqrt{26}$.

Now apply the definition of speed, the rate of change in distance, to get

$v = \frac{x}{t} = \frac{\sqrt{26}}{2} = 2.55 u n i t s / s$