What is scalar product of a=2i-3j, b=6i+4j?

Expert Answers

An illustration of the letter 'A' in a speech bubbles

Remember the formula of dot scalar product:

`bar a` * `barb` = |bara|*|barb|*cos theta

theta is the angle between bara and barb

|a| is the magnitude of the vector a: bara = sqrt(2^2 + (-3)^2)

bara = sqrt 13

|b| is the magnitude of the vector b:

 `barb = sqrt(6^2 + 4^2)`...

Unlock
This Answer Now

Start your 48-hour free trial to unlock this answer and thousands more. Enjoy eNotes ad-free and cancel anytime.

Start your 48-Hour Free Trial

Remember the formula of dot scalar product:

`bar a` * `barb` = |bara|*|barb|*cos theta

theta is the angle between bara and barb

|a| is the magnitude of the vector a: bara = sqrt(2^2 + (-3)^2)

bara = sqrt 13

|b| is the magnitude of the vector b:

 `barb = sqrt(6^2 + 4^2)` `bara = sqrt 52 = 2sqrt13`

`` `bara*barb = (sqrt13)*(2sqrt13) cos theta`

The scalar product is `bara*barb`  =26 cos `theta`  .

Approved by eNotes Editorial Team