document.write( "Question 898382: How and why is the equation under the link true
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\n" ); document.write( "The i stands for imaginary unit. My teacher solved the whole problem on the board but didn't explain how he did this particular equation.
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Algebra.Com's Answer #544814 by Alan3354(69443)\"\" \"About 
You can put this solution on YOUR website!
Because cis(v)/cis(u) = cis(v-u)
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