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(-2+2^x)/(-1+x)

Limit of the function (-2+2^x)/(-1+x)

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The solution

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     /      x\
     |-2 + 2 |
 lim |-------|
x->1+\ -1 + x/
$$\lim_{x \to 1^+}\left(\frac{2^{x} - 2}{x - 1}\right)$$
Limit((-2 + 2^x)/(-1 + x), x, 1)
Lopital's rule
We have indeterminateness of type
0/0,

i.e. limit for the numerator is
$$\lim_{x \to 1^+}\left(2^{x} - 2\right) = 0$$
and limit for the denominator is
$$\lim_{x \to 1^+}\left(x - 1\right) = 0$$
Let's take derivatives of the numerator and denominator until we eliminate indeterninateness.
$$\lim_{x \to 1^+}\left(\frac{2^{x} - 2}{x - 1}\right)$$
=
$$\lim_{x \to 1^+}\left(\frac{\frac{d}{d x} \left(2^{x} - 2\right)}{\frac{d}{d x} \left(x - 1\right)}\right)$$
=
$$\lim_{x \to 1^+}\left(2^{x} \log{\left(2 \right)}\right)$$
=
$$\lim_{x \to 1^+}\left(2 \log{\left(2 \right)}\right)$$
=
$$\lim_{x \to 1^+}\left(2 \log{\left(2 \right)}\right)$$
=
$$2 \log{\left(2 \right)}$$
It can be seen that we have applied Lopital's rule (we have taken derivatives with respect to the numerator and denominator) 1 time(s)
The graph
One‐sided limits [src]
     /      x\
     |-2 + 2 |
 lim |-------|
x->1+\ -1 + x/
$$\lim_{x \to 1^+}\left(\frac{2^{x} - 2}{x - 1}\right)$$
2*log(2)
$$2 \log{\left(2 \right)}$$
= 1.38629436111989
     /      x\
     |-2 + 2 |
 lim |-------|
x->1-\ -1 + x/
$$\lim_{x \to 1^-}\left(\frac{2^{x} - 2}{x - 1}\right)$$
2*log(2)
$$2 \log{\left(2 \right)}$$
= 1.38629436111989
= 1.38629436111989
Other limits x→0, -oo, +oo, 1
$$\lim_{x \to 1^-}\left(\frac{2^{x} - 2}{x - 1}\right) = 2 \log{\left(2 \right)}$$
More at x→1 from the left
$$\lim_{x \to 1^+}\left(\frac{2^{x} - 2}{x - 1}\right) = 2 \log{\left(2 \right)}$$
$$\lim_{x \to \infty}\left(\frac{2^{x} - 2}{x - 1}\right) = \infty$$
More at x→oo
$$\lim_{x \to 0^-}\left(\frac{2^{x} - 2}{x - 1}\right) = 1$$
More at x→0 from the left
$$\lim_{x \to 0^+}\left(\frac{2^{x} - 2}{x - 1}\right) = 1$$
More at x→0 from the right
$$\lim_{x \to -\infty}\left(\frac{2^{x} - 2}{x - 1}\right) = 0$$
More at x→-oo
Rapid solution [src]
2*log(2)
$$2 \log{\left(2 \right)}$$
Numerical answer [src]
1.38629436111989
1.38629436111989
The graph
Limit of the function (-2+2^x)/(-1+x)