SOLUTION: find the modulas and argument of 7-i/3-4i

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Question 862188: find the modulas and argument of 7-i/3-4i
Found 2 solutions by Fombitz, Edwin McCravy:
Answer by Fombitz(32388) About Me  (Show Source):
Answer by Edwin McCravy(20064) About Me  (Show Source):
You can put this solution on YOUR website!



7-i%2F3-4i

7+-+%281%2F3%2B4%29i

7+-+%284%261%2F3%29i

7-%2813%2F3%29i

Modulus = sqrt%287%5E2%2B%28-13%2F3%29%5E2%29 = sqrt%2849%2B169%2F9%29 = sqrt%28%28441%2B169%29%2F9%29 = sqrt%28610%2F9%29 = sqrt%28610%29%2F3

Argument = tan-1%28-13%2F3%29%2F7 = tan-1%28-13%2F3%29%2A%28-1%2F7%29 = tan-1%28-13%2F21%29

This is a fourth quadrant angle since (7,-13%2F3%29) is in the fourth 
quadrant, so the argument is approximately 328.2° or -.554 radians. 

Edwin