Limit Infinity Question

Jason76

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Oct 19, 2012
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Where \(\displaystyle n = \) a real number

\(\displaystyle n - \infty = ?\)

\(\displaystyle n + \infty = ?\)

\(\displaystyle \infty + n = ?\)

\(\displaystyle \infty - n = ?\)

\(\displaystyle \infty - \infty = ?\)

\(\displaystyle \dfrac{\infty}{n} = ?\)

\(\displaystyle \dfrac{\infty}{0} = ?\)

\(\displaystyle \infty + 0 = ?\)

\(\displaystyle 0 + \infty = ?\)

Here are some I already know:

\(\displaystyle \dfrac{0}{0} =\) Indeterminate

\(\displaystyle \dfrac{0}{\infty} = 0\)

\(\displaystyle \dfrac{n}{\infty} = 0\)

\(\displaystyle \dfrac{\infty}{\infty} = \infty\)

\(\displaystyle (\infty)(\infty) = \infty\)

\(\displaystyle (n)(\infty) = \infty\)

\(\displaystyle (0)(\infty) = \) Indeterminate

\(\displaystyle 0 - \infty = -\infty\)

\(\displaystyle \infty - 0 =\) Indeterminate

\(\displaystyle \infty + \infty = \infty\)
 
Last edited:
Where \(\displaystyle n = \) a real number

\(\displaystyle n - \infty = ?\)

\(\displaystyle n + \infty = ?\)

\(\displaystyle \infty + n = ?\)

\(\displaystyle \infty - n = ?\)

\(\displaystyle \infty - \infty = ?\)

\(\displaystyle \dfrac{\infty}{n} = ?\)

\(\displaystyle \dfrac{\infty}{0} = ?\)

\(\displaystyle \infty + 0 = ?\)

\(\displaystyle 0 + \infty = ?\)

Here are some I already know:

\(\displaystyle \dfrac{0}{0} =\) Indeterminate

\(\displaystyle \dfrac{0}{\infty} = 0\)

\(\displaystyle \dfrac{n}{\infty} = 0\)

\(\displaystyle \dfrac{\infty}{\infty} = \infty\)... NO

\(\displaystyle (\infty)(\infty) = \infty\)

\(\displaystyle (n)(\infty) = \infty\)

\(\displaystyle (0)(\infty) = \) Indeterminate

\(\displaystyle 0 - \infty = -\infty\)

\(\displaystyle \infty - 0 =\) Indeterminate... NO

\(\displaystyle \infty + \infty = \infty\)
Guess the others?

HINT: only ONE of them is indeterminate.
 
Zero times infinity is sometimes defined to be zero. It depends on the context. For limits you are correct, it is treated as indeterminate
 
Zero times infinity is sometimes defined to be zero. It depends on the context. For limits you are correct, it is treated as indeterminate

Please give me an example of a context where it evaluates to 0, and when infinity.
 
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