Let u = and v = . Find 3u - 4v?

Question

Let u = <3.-4> and v = <2,-3>. Find 3u - 4v?

whpalmer4 · Answer

This is a lot like multiplying binomials by numbers: $$u=<3,-4>$$$$3u = <3*3,3*-4> = <9,-12>$$ Do the same to find the value of -4v, then subtract, with the first component of the result being the first component of u - the first component of v, and the second component of the result being the second component of u - the second component of v. Does that make sense?

anonymous · Answer

some what...

whpalmer4 · Answer

For example, if we were to find 2u + 4v, here's what we do: 2u: 2*<3,-4> -> <6,-8> 4v: 4*<2,-3> -> <8,-12> 2u+4v = <6+8,-8+(-12)> = <14, -20>

whpalmer4 · Answer

Easy, right?

whpalmer4 · Answer

Remember that we are dealing with vectors, and u=<3,-4> can be thought of as "right 3, down 4", so 3u would be "right 3*3, down 3*4", and adding or subtracting is just hooking them up in a chain...

anonymous · Answer

that makes more sense. Im sorry im more asleep then awake but I need to know things like these for a final

whpalmer4 · Answer

what else can I help you with before you do a face plant on your keyboard? :-)

zzr0ck3r · Answer

lol

whpalmer4 · Answer

attachment

kenljw · Answer

A way to think of vectors is there complex numbers, your just doing algebra.