Help writing an equation that satisfies some statements

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SUMMARY

The discussion centers on constructing a mathematical function that meets specific criteria, including a defined domain of (-∞, 0) U (0, ∞), continuity except at x = 0, and specific limits at x = 1. The proposed function, f(x) = (x + 1)/x, satisfies the domain and continuity requirements, as well as f(1) = 2. However, participants highlight a contradiction in the limits at x = 1, indicating that the function cannot be continuous at that point while also meeting the specified limits of -∞ from the left and 0 from the right.

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Homework Statement


how do u approach a question like that?

write an equation that satisfy the following simultaneously

a) the domain of f is (-Infinity, 0) U (0,infinity)
b) f is continuous on its domain (that is everywhere except at x = 0)
c) lim f(x) as x--> 1- (from the left) = - infinti
d) lim f(x) as x --> 1+ (from the right) = 0
e) f(1) = 2.



The Attempt at a Solution



i know from the domain that x can't be zero
so the equation is probably going to a fraction, let say (x+1)/x.
(x+1)/x domain is (-Infinity, 0) U (0,infinity) and its continuous on its domain.
f(1) = (1+1)/1 = 2/1 = 2.
so a, b, and e are correct
but c and d, i don't know how to do them.
any help?
 
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welcome to pf!

hi ammsa! welcome to pf! :smile:

(have an infinity: ∞ :wink:)
ammsa said:
a) the domain of f is (-Infinity, 0) U (0,infinity)
b) f is continuous on its domain (that is everywhere except at x = 0)
c) lim f(x) as x--> 1- (from the left) = - infinti
d) lim f(x) as x --> 1+ (from the right) = 0
e) f(1) = 2.

no, the question must be wrong :redface:

"b) f is continuous on its domain (that is everywhere except at x = 0)" is inconsistent with c) d) and e) …

those three conditions clearly make the function discontinuous at x = 1 :frown:
 

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