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-x^2+3*x

Limit of the function -x^2+3*x

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     /   2      \
 lim \- x  + 3*x/
x->oo            
$$\lim_{x \to \infty}\left(- x^{2} + 3 x\right)$$
Limit(-x^2 + 3*x, x, oo, dir='-')
Detail solution
Let's take the limit
$$\lim_{x \to \infty}\left(- x^{2} + 3 x\right)$$
Let's divide numerator and denominator by x^2:
$$\lim_{x \to \infty}\left(- x^{2} + 3 x\right)$$ =
$$\lim_{x \to \infty}\left(\frac{-1 + \frac{3}{x}}{\frac{1}{x^{2}}}\right)$$
Do Replacement
$$u = \frac{1}{x}$$
then
$$\lim_{x \to \infty}\left(\frac{-1 + \frac{3}{x}}{\frac{1}{x^{2}}}\right) = \lim_{u \to 0^+}\left(\frac{3 u - 1}{u^{2}}\right)$$
=
$$\frac{-1 + 0 \cdot 3}{0} = -\infty$$

The final answer:
$$\lim_{x \to \infty}\left(- x^{2} + 3 x\right) = -\infty$$
Lopital's rule
There is no sense to apply Lopital's rule to this function since there is no indeterminateness of 0/0 or oo/oo type
The graph
Rapid solution [src]
-oo
$$-\infty$$
Other limits x→0, -oo, +oo, 1
$$\lim_{x \to \infty}\left(- x^{2} + 3 x\right) = -\infty$$
$$\lim_{x \to 0^-}\left(- x^{2} + 3 x\right) = 0$$
More at x→0 from the left
$$\lim_{x \to 0^+}\left(- x^{2} + 3 x\right) = 0$$
More at x→0 from the right
$$\lim_{x \to 1^-}\left(- x^{2} + 3 x\right) = 2$$
More at x→1 from the left
$$\lim_{x \to 1^+}\left(- x^{2} + 3 x\right) = 2$$
More at x→1 from the right
$$\lim_{x \to -\infty}\left(- x^{2} + 3 x\right) = -\infty$$
More at x→-oo
The graph
Limit of the function -x^2+3*x