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

Options

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

Correct answer

A. x = y 1+ y

Step-by-step solution

y=x+x^2+x^3+ upto infinite terms. x+x^2+x^3+ is a G.P. with a=x and r=x . aligned & y= x 1-x & y-x y=x aligned aligned & x+x y=y & x(1+y)=y & x= y 1+y aligned

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