- #1

chwala

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## Homework Statement

if ## x + iy## = ## \frac a {b+ cos ∅ + i sin ∅} ##

then show that

##(b^2-1)(x^2+y^2)+a^2 = 2abx##

## Homework Equations

## The Attempt at a Solution

i let ## ... ##x + iy = ## \ a(b+cos ∅ - i sin ∅)##/ ##(b + cos ∅)^2 + sin^2∅ ##.......got stuck here....

alternatively i let

## b + cos ∅ + i sin ∅## = ## a/(x +iy)## then it follows that

## b+ cos ∅ + i sin ∅## = ## a(x-iy)/(x^2 +y^2)##

## x^2 + y^2 = a(x-iy)/ (b+ cos ∅+ i sin ∅)##...advise stuck again...am i doing something wrong...

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