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Finding the range of reciprocal graphs

How do I find the range of the graph

(2x-3)/(x-2)
for x > 2


thanks
Reply 1
you can rewrite it as (2x - 4 )/(x -2) + 1/(x - 2)

===> 2 + 1/(x - 2)

after that you should be able to figure it out by comparing with f(x) = 1/x
Original post by the bear
you can rewrite it as (2x - 4 )/(x -2) + 1/(x - 2)

===> 2 + 1/(x - 2)

after that you should be able to figure it out by comparing with f(x) = 1/x


is this the best way to do it?
is there any other way???
Reply 3
Original post by jsmith6131
is this the best way to do it?
is there any other way???


you could let x become v.large and notice that y tends to a certain value; i prefer my other method
Original post by the bear
you could let x become v.large and notice that y tends to a certain value; i prefer my other method


nice!
thanks
Reply 5
You can divide through by x to give the following

f(x)=2x3x2=23x12xf(x) = \dfrac{2x-3}{x-2} = \dfrac{2-\frac{3}{x}}{1-\frac{2}{x}}

As x tends towards infinity 1/x tends towards 0 so that f(x) tends towards 2 so f(x)>2

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