#Why is this c?

52 messages · Page 1 of 1 (latest)

green steepleBOT
tawdry leaf
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because there will be some value between -inf and inf, where the denominator become 0

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and at that point, the function breaks

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so, its not continuous at that point

gentle pilot
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how so?

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can u give me an example?

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but i do understand what u mean, i just need a clarification

tawdry leaf
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see, polynomials, in most cases have a root. no?

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the denominator in option C is a polynomial

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of degree 4

gentle pilot
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do you mean like even root thing

tawdry leaf
gentle pilot
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so - inf ^ 4 would be -inf x -inf x -inf x -inf, wouldn't that be positive?

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if the polynomial is even, wouldn't negative inf or positive inf have the same positive inf outcome, therefore when dividing, it would be continuous no?

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i agree my logic is flawed somewhere, just trying to pinpoint where..

tawdry leaf
gentle pilot
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hmm so it would not be continuous since the even polynomial would result in a positive number outcome, therefore wouldn't be continuous for negative intervals? or am i going far off

tawdry leaf
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is the first term in denominator x^5 or x^6?

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i'll graph it and show it to you

gentle pilot
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sorry if it isnt clear,

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it is x^6

tawdry leaf
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alr

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this is wut the denominator's graph would look like

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you see that there are 2 values of x where the expression is 0?

gentle pilot
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yeah

tawdry leaf
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at those points, h(x) would become 1/0

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which is undefined

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and the graph breaks there

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so, it is not continuous at that point

gentle pilot
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ohhh i kind of see what you mean

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i understand from a graphical dimension , but how would you figure it out with just the function itself?

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im guessing it would be applicable for every polynomial?

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(if it is below 0)

tawdry leaf
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yeah, so look, you just need to know one thing. for a continuous graph, the func should be defined at all points. (this is true if it is a polynomial function)
so, if there is any point where you see that the func is not defined, the graph wont be continuous

tawdry leaf
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so, your job in these cases, where a polynomial is in den.
is to see if any roots to that polynomial exist or no

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if it does, graph is not continuous

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else it is

gentle pilot
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ok thanks

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last question, Does the answer mean from the range -5 to 0, and both has to meet the condition of,

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x<=-1 and -1 < x <= 0?

tawdry leaf
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this is a question on limits

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have you learnt them yet?

gentle pilot
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yes

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just to make sure

tawdry leaf
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yeah. so you just need to see if the limits at the breaking points are same or no

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if they are, it'll be continuous

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or else no

gentle pilot
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ok gotchu