>>8032518First learn what everything means:
They're giving you a force, which is a vector.
A vector is like an arrow, it points in a certain direction and has a certain length.
An easy way to represent this vector in a plane is by defining two standard vectors, each of length 1. These are the vector in the x direction, i, and the vector in the y direction, j.
So if I want to write down a vector that goes 3 to the right (in the x axis direction) and 2 down (in the y axis direction), I would write this vector as 3i-2j.
There are special types of vectors called unit vectors, that point in some direction, but have length exactly 1.
The length can be calculated by drawing the vector in question and applying pythagoras theorem. If you draw the previous example, 3 to the right and 2 down, you can draw a right angled triangle with lengths 3 and 2, and the hypotenuse is the length of the vector, so length = sqrt(3^2+2^2).
To make the vector 3i-2j into a unit vector, divide each individual component by the length of the vector. Therefore the unit vector of 3i-2j is 3/sqrt(3^2+2^2) i -2/sqrt(3^2+2^2) j.
A similar consideration with trigonometry can give you the angle relative to the x axis. In this case, the angle would be arctan(-2/3).
Always remember that it's very helpful to draw the vector starting at the origin to find out the angle and length.
Good luck
