Task/26411448
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( (x+3)/(x-3) - x/(x+3) ) : (x+1) / (x+3) =
( (x+3)² -x(x-3) ) / (x-3)(x+3) * (x+3) /(x+1) =
( x²+6x+9 - x²+3x )/(x-3)(x+3) *(x+3) /(x+1) =(9x+9)/(x-3)(x+3) *(x+3) /(x+1)=
9(x+1)(x+3) /(x-3)(x+3) (x+1) =9 /(x-3).
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(x+3) / (x-3) - x / (x+3) = ( (x+3)² -x(x-3) )/(x-3)(x+3) =
( x²+6x+9 - x²+3x ) / (x-3)(x+3) =9(x+1) / (x-3)(x+3)
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9(x+1) / (x-3)(x+3) :(x+1) /(x+3) =9(x+1) /(x-3)(x+3) *(x+3) / (x+1) =
9(x+1)(x+3)/(x-3)(x+3)(x+1) = 9 /(x-3) .
