SOLUTION: Find modulus of complex number z= (((3-4j)(3j-2))/-j) i have tried =((9j-6-12j^2+8j)/-j) =((17j+6)/-j) modulus = (sqrt(17^2 +6^2))/-j = (sqrt(325))/-j Is this correct

Algebra ->  Complex Numbers Imaginary Numbers Solvers and Lesson -> SOLUTION: Find modulus of complex number z= (((3-4j)(3j-2))/-j) i have tried =((9j-6-12j^2+8j)/-j) =((17j+6)/-j) modulus = (sqrt(17^2 +6^2))/-j = (sqrt(325))/-j Is this correct      Log On


   



Question 1136493: Find modulus of complex number z= (((3-4j)(3j-2))/-j)
i have tried
=((9j-6-12j^2+8j)/-j)
=((17j+6)/-j)
modulus = (sqrt(17^2 +6^2))/-j = (sqrt(325))/-j
Is this correct

Found 2 solutions by rothauserc, greenestamps:
Answer by rothauserc(4718) About Me  (Show Source):
You can put this solution on YOUR website!
z = (((3-4j)(3j-2))/-j) =
:
perform complex number division
:
Note this problem uses j instead of i, therefore j = square root(-1) and j^2 = -1
:
multiply numerator and denominator by j
:
(((3-4j)(3j-2))/-j) * (j/j) =
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Note the denominator becomes -j^2 = -(-1) = 1
:
(((3-4j)(-2+3j)) * j =
:
perform complex number multiplication
:
(-6 +9j +8j -12j^2) * j =
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(-6 +9j +8j +12) * j =
:
(6 +17j) * j =
:
6j -17 =
:
-17 +6j
:
************************************************
modulus = square root( (-17)^2 + 6^2 ) = 18.0278
************************************************
:

Answer by greenestamps(13203) About Me  (Show Source):
You can put this solution on YOUR website!


You don't need to simplify the given complex expression, because for complex numbers A, B, and C,

mod%28%28A%2AB%29%2FC%29+=+%28mod%28A%29%2Amod%28B%29%29%2Fmod%28C%29

= 18.028 to 3 decimal places.