How do you evaluate the limit of $lim (-x^3+3x^2-4)$ as $x->-1$ ?

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Answer 1 · 2017-06-13T12:26:33

$:. x rarr (-1) lim(-x^3+3x^2-4) =0$

$: x rarr (-0.9999) lim(-x^3+3x^2-4) = -0.0009$

$x rarr (-1^+) lim(-x^3+3x^2-4) = lim(-(-1)^3+3(-1)^2-4) = 0$

$: x rarr (-1.0001) lim(-x^3+3x^2-4) = 0.0009$

$x rarr (-1^-) lim(-x^3+3x^2-4) = lim(-(-1)^3+3(-1)^2-4) = 0$

$:. x rarr (-1) lim(-x^3+3x^2-4) =0$ [Ans]

Answer 2 · 2017-06-13T18:10:23

$0$

$"the limit of a polynomial can be evaluated by substitution"$

$rArrlim_(xto-1)(-x^3+3x^2-4)$

$=-(-1)^3+3(-1)^2-4$

$=0$

How do you evaluate the limit of lim (-x^3+3x^2-4)lim (-x^3+3x^2-4) as x->-1x->-1?