SOLUTION: Multiply (-2 cis 75°)(3 cis-45°) and express the answer in rectangular coordinates. A)(3√6/2)+(3√2/2i) B)-3√3-3i C)(3√3/2)-9/2i D)-√3+i I mul

Algebra ->  Trigonometry-basics -> SOLUTION: Multiply (-2 cis 75°)(3 cis-45°) and express the answer in rectangular coordinates. A)(3√6/2)+(3√2/2i) B)-3√3-3i C)(3√3/2)-9/2i D)-√3+i I mul      Log On


   



Question 943988: Multiply (-2 cis 75°)(3 cis-45°) and express the answer in rectangular coordinates.
A)(3√6/2)+(3√2/2i)
B)-3√3-3i
C)(3√3/2)-9/2i
D)-√3+i
I multiplied those and got -6 cis 30°, but now I'm having trouble figuring out how to convert it.

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Multiply (-2 cis 75°)(3 cis-45°) and express the answer in rectangular coordinates.
A)(3√6/2)+(3√2/2i)
B)-3√3-3i
C)(3√3/2)-9/2i
D)-√3+i
I multiplied those and got -6 cis 30°, but now I'm having trouble figuring out how to convert it.
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-6cis(30) = -6cos(30) - 6i*sin(30)
= -3sqrt(3) - 3i