Question 207865
y=1/{1-1/(1-x) }
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y= 1/{(1-x)-1}/(1-x),,,,,,invert  and  multiply
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y=1 * (1-x)/(-x)
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y=(1-x)/(-x),,,,,cross  multiply
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-xy = 1-x
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x-xy=1
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x(1-y) =1
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x= 1/(1-y)
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check,,,Let  x=2,,,y in original  and  answer  = 1/2,,,,,ok
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