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Complex Numbers

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For this question, I'm just wondering whether there is a much simpler way to solve for x and y rather than treating the 2 fractions separately and multiplying by the complex conjugates for each.
Original post by As_Dust_Dances_
Picture2.png

For this question, I'm just wondering whether there is a much simpler way to solve for x and y rather than treating the 2 fractions separately and multiplying by the complex conjugates for each.


In this case, yes there is.

Move the 1/(1+2i) to the RHS via subtraction.

Put the RHS over a common denominator and simplify.

Invert both fractions and simplify the RHS.
Reply 2
First write

1x+iy=2i1+2i\frac 1 {x+iy} = \frac{2i}{1 + 2i}

Then multiply the top and bottom of the RHS by 12i\frac 1{2i} ...might save a little time.
Original post by jb444
First write

1x+iy=2i1+2i\frac 1 {x+iy} = \frac{2i}{1 + 2i}

Then multiply the top and bottom of the RHS by 12i\frac 1{2i} ...might save a little time.


Unfortunately I don't have the answer at hand, but I'm getting x = 1 and y = -1/2 (is this correct from your calculations?)
Original post by As_Dust_Dances_
Unfortunately I don't have the answer at hand, but I'm getting x = 1 and y = -1/2 (is this correct from your calculations?)


Yes.
Original post by ghostwalker
Yes.


Thanks for your help :smile:

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