Question

What is the length (magnitude) of the vector (2,-1)?

Answer 1

It is in the picture, I hope this help!

Answer 2

`\[√(5)\]`

Explanation:

The given vector is represented by (2,-1).

This can be represented in general form as (x,y) where x=2 and y=-1.

Magnitude of the vector represented as (x,y) is given by
`[\sqrt{x^(2)+y^(2)}\]`

Evaluating for the given values of x and y,

`\[\sqrt{2^(2)+(-1)^(2)}\]`
`\[=√(4+1)\]`

`\[=√(5)\]`

Length of the vector is
`\[√(5)\]`