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Clearing the inner fraction resolves the limit by simplifying the complex rational expression into a polynomial form. Near $x=-1$, with $x\ne-1$, multiplying the numerator and denominator of $\frac{3+3x}{1/x+1}$ by $x$ gives $\frac{3x+3x^2}{1+x}$.

Conditions: The limit is as $x \to -1$.; The expression contains an inner fraction $1/x$ in the denominator.; Multiplication by $x$ is valid for $x \ne 0$, and specifically near $x=-1$ where $x \ne 0$.; The original expression is undefined at $x=-1$ (indeterminate form $0/0$).

Clearing the inner fraction resolves the limit by simplifying the complex rational expression into a polynomial form. Near $x=-1$, with $x\ne-1$, multiplying the numerator and denominator of $\frac{3+3x}{1/x+1}$ by $x$ gives $\frac{3x+3x^2}{1+x}$.

Conditions: The limit is as $x \to -1$.; The expression contains an inner fraction $1/x$ in the denominator.; Multiplication by $x$ is valid for $x \ne 0$, and specifically near $x=-1$ where $x \ne 0$.; The original expression is undefined at $x=-1$ (indeterminate form $0/0$).