Math Help - Finding a Vector

Find a vector of length 3 which has:
a) the same direction as 5i + 2j
b) the opposite direction to 4i + 5j


then

the is square root...but I don't know how to show that on here. is my math correct?

and is b) done the same way except I would multiply the whole thing by -1?

Thanks

to need to learn this.
So the vector you want is

Originally Posted by Plato

to need to learn this.
So the vector you want is

ah, okay, so my math was correct.
I'll go ahead and assume the same format is used for b), but it's negative.

Thanks