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If x=1-y+y^2-y^3+ . up to infinite terms, where |y| 1 then which one of the following is correct?

Options

  1. Ax= 1 1+y
  2. Bx= y 1-y
  3. Cx= y 1+y
  4. Dx= y 1-y

Correct answer

A. x= 1 1+y

Step-by-step solution

x=1-y+y^2-y^3+ . up to infinite terms. We can see that the given series is geometric progression, with a =1 and r =- y aligned & S _ = a 1- r = 1 1-(- y ) = 1 1+ y & x = 1 1+ y . aligned

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