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October 19, 2025, 01:27:17 pm

Author Topic: Need help on a question  (Read 509 times)  Share 

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rawrness

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Need help on a question
« on: April 25, 2013, 04:12:45 pm »
0
Find the inverse of the function
f(x) = 1- x/a, 0<a<1
Sketch f(x) and f^-1(x) (inverse) on the one set of axes
Find the point of intersection graphically and algebraically.

Please help and thanks in advance :3

Zealous

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Re: Need help on a question
« Reply #1 on: April 25, 2013, 05:10:54 pm »
+1
I'll do the easier part (finding the inverse) =p.. for the sketching I'm not sure since we have an idea of where a will be but we do not know for sure the value of a.



Swap x and y.

... simplify
... subtract 1 and divide by -1.



So the inverse



Now for sketching I'm not sure if you can even sketch it without knowing a.
In f(x) a is on the denominator, so if a is between 0 and 1, we could simply say a is 0.01 and the gradient will be -100 (very steep) or the line could almost look horizontal, so I'll let one of the fancy pants mathematicians take it from here.
« Last Edit: April 25, 2013, 05:15:29 pm by Ovazealous »
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Daenerys Targaryen

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Re: Need help on a question
« Reply #2 on: April 25, 2013, 05:32:09 pm »
0
I'll do the easier part (finding the inverse) =p.. for the sketching I'm not sure since we have an idea of where a will be but we do not know for sure the value of a.



Swap x and y.

... simplify
... subtract 1 and divide by -1.



So the inverse



Sketching:




Because the intercepts of 'a' will be less than the 1 and above 0

For POI:
Let


« Last Edit: April 25, 2013, 05:36:49 pm by HatersGonnaHate »
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