How do you find the range of the function $y=2x^2+1$ when the domain is {9, 3, 99}?

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Answer 1 · 2015-06-19T14:52:43

This function has a range between $19$ an $19603$

The domain of the function has only 3 elements, so it will be easy just to calculate the values:

$f(3)=2*3^2+1=2*9+1=18+1=19$
$f(9)=2*9^2+1=2*81+1=162+1=163$
$f(99)=2*99^2+1=2*9801+1=19602+1=19603$

So the function has only the values from range: $<19;19603>$

Answer 2 · 2015-06-19T16:35:01

For a function with finite domain, evaluate the function at each value. The set of results is the range.

The range of a function is the set of all values the function attains (the set of 'y-values' or of 'outputs')

For the function given, we find:
$f (9)=163$
$f (3)=19$
$f (99)=19 603$
So the range is ${163, 19, 19603}$ ,

How do you find the range of the function y=2x^2+1y=2x^2+1 when the domain is {9, 3, 99}?