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Discussion Response Post to: FUNCTIONS

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Bipin Dubey (13679)

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Graphical approach clearly shows that it is not one-one.

If its an objective question u can proceed in this way :
y = (x²+4x+30)/(x²-8x+18)
as x tends to minus infinity y tends to 1.
as x tends to plus infinity y tends to 1.
Hence there will be at least one maxima in between.
But for a function to be one-one it should be either increasing or decreasing.
Hence it is not one-one.

Bipin Kumar Dubey Chemical Dept. IIT Kharagpur

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