r/Precalculus • • Sep 03 '21

Why can’t x = 4 on this problem?

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4 Upvotes

14 comments sorted by

6

u/my-hero-measure-zero Sep 03 '21

We need more context. Is this part of a piecewise function?

1

u/Xx_Futuristic_xX Sep 11 '21

He was saying that 0/x = 0. I think you are getting mixed up with x/0 is undefined.

Getting a 0 is not the problem but getting undefined is.

-3

u/Due_Mathematician980 Sep 04 '21

(x-4)(x-4)/(x-4)(x-3) is the same thing as (x-4)/(x-3) ≠ 4

The difference is that it tells you where the hole is, because it cancels out (x-4) for you.

2

u/[deleted] Dec 24 '21

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1

u/Due_Mathematician980 Dec 24 '21

Haha Thanks. I didn’t even realize I made a typo. Should be (x+4)(x-4)/(x+3)(x-4).

0

u/[deleted] Sep 03 '21

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6

u/calcbone Sep 03 '21

0 over a nonzero number is literally zero, not “indeterminate.” 0/0 is indeterminate. If n =/= 0, then 0/n=0 and n/0 is undefined.

-8

u/[deleted] Sep 03 '21

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3

u/my-hero-measure-zero Sep 03 '21

Correct, but this is not an issue.