Question 776314: Please help me solve this problem with solutions so i can understand clearly: Found 2 solutions by stanbon, josmiceli:Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! (7-5i)/(3+6i)
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Multiply numerator and denominator by (3-6i) to get:
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= [(7-5i)(3-6i)]/[3^2+6^2]
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= [21-42i-15i-30]/45
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= (-9-57i)/45
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Cheers,
Stan H.
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You can put this solution on YOUR website!
What you are trying to do is to get this
into the form
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Multiply both top and bottom by
This is called the complex conjugate
This is the same as multiplying by ,
so you haven't changed anything
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Rewrite it as:
Now multiply out the denominator as follows:
Using the fact that , I get:
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Now my expression is:
Now multiply out the numerator:
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Putting the numerator and denominator
together, I get: , or
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I can check this result:
Multiply both sides by
OK
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