Question

Two forces are given by j = (-2,1] and K = (-5,3), in
Newtons. What is the magnitude of j+k ?

Answer 1

`√(65)`

Explanation:

The magnitude of a vector < x, y > is calculated as

| < x, y > | =
`√(x^2+y^2)`

Thus

j + k = < - 2, 1 > + < - 5, 3 > = < - 2 - 5, 1 + 3 > = < - 7, 4 >

Then

| < - 7, 4 > | =
`√((-7)^2+4^2)` =
`√(49+16)` =
`√(65)`