If a = 3i + 2j and b=-2i+j calculate

Question

|a+b|
a and b are vectors and i and j have the arrow pointy thing above it instead of the dots.

The correct answer is square root 11.

So, what I did was substitute a + b with the equations:
=(3i+2j-k)+(-2i+j)
=i+3j-k

Now I'm stuck and don't know what to do.

I tried solving it by making all i, j, and k's ones, which got me 3.

Do I plug in values into i, j and k?

Because there aren't any other values given in the question...

Answer 1

|i+3j-k| = √(1+9+1) = √11

Better go back to where it shows how to figure the length of a vector.