Find the magnitude and direction of each vector

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joemama69
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Homework Statement


2. You are given three vectors: A = (6.0i— 8.0j) units B = (-8.0i + 3.0j) units and C = (26.0i + 19.0j) units.

a) Find the magnitude and direction of each vector.


b) Find the resultant of A + B, A - B and A + B - C.

c) It is know that aA + bB + C = 0. Find the values of a and b that satisfy this vector equation.


Homework Equations





The Attempt at a Solution



For part A, what does it mean to find the direction of each vector. do they want the angle
 
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joemama69 said:

Homework Statement


2. You are given three vectors: A = (6.0i— 8.0j) units B = (-8.0i + 3.0j) units and C = (26.0i + 19.0j) units.

a) Find the magnitude and direction of each vector.


b) Find the resultant of A + B, A - B and A + B - C.

c) It is know that aA + bB + C = 0. Find the values of a and b that satisfy this vector equation.


Homework Equations





The Attempt at a Solution



For part A, what does it mean to find the direction of each vector. do they want the angle

yes they do
 


I assume they want the angle of the vector. By convention, the angle is measured counter-clockwise from the positive x axis. Think of how you drew the unit circle in trigonometry.

For B, you simply add components.

Part C, you Have what appears to be one equation and two unknowns. However, it's a vector equation, which in your case is actually two equations. There's one for your x components and one for your y components.
 


so i would do

a(6.0i— 8.0j) +b(-8.0i + 3.0j) + (26.0i + 19.0j) = 0

6a - 8b + 26 = 0

-8a + 3b + 19 = 0 and just solve this system