Question

What is `|| <1, 6, -3 > - < 4, -2, -9 >||`?

Answer 1

`||<<1, 6, -3>> - <<4, -2, -9>>|| = sqrt( 109 )`

Explanation:

Let:

`vec u = <<1, 6, -3>> - <<4, -2, -9>>`

First we will simplify the vector:

`vec u = <<(1)-(4), (6)-(-2), (-3)-(-9)>>`
`" " = <<-3, 8, 6>>`

Then we compute the norm:

`||vec u|| = sqrt( (-3)^2+(8)^2+(6)^2)`
`" " = sqrt( 9+64+36 )`
`" " = sqrt( 109 )`