Question

Find a ⋅ b.
a = 8i + 6j, b = 4i + 5j

Answer 1

You are to just mutiply them..

Do you know about FOIL??

Answer 2

yes but the answer choices are numbers! i know i as an imaginary number but j as a variable and i think they are both variables in the problem.

Answer 3

If i is an imaginary here then :

\[-32 + 64i.j + 30j^2\]

Answer 4

its not...............
the answer is a digit....... idk what it is

Answer 5

no its somethign to do with dot products and vectors

Answer 6

\[a \color{red} {\cdot} b = |ab|\cos(\theta)\]

Answer 7

Or simply mutiply i coefficient with i and j with j..

\[a \cdot b = 8 \times 4 + 6 \times 5 \implies \color{green}{32 + 30} = ??\]

Answer 8

yes!!! thank you!!!

Answer 9

Got it right or not?

Answer 10

yep:)

Answer 11

now do you know if i am multiplying v *w and v = <3, -8, -3>; w = <-4, -2, -6> how do i solve this?

Answer 12

like do i multiply v1*w1 + v2w2+v3w3?

Answer 13

Is it \(v \cdot w\) or \(v \times w\) ??

Answer 14

v⋅w

Answer 15

Yes just multiply the corresponding elemets there..

Answer 16

Yes, as you are saying go like that... v1*w1 + v2......... and so on..

Answer 17

thank you:)