Find the domain and range for each quadratic function.

a. y = x^2 – 6x +5

b. y = 3x^2 + 2x +9

Printable View

- August 2nd 2006, 07:53 PMpashahDomain and Range
Find the domain and range for each quadratic function.

a. y = x^2 – 6x +5

b. y = 3x^2 + 2x +9 - August 2nd 2006, 10:29 PMCaptainBlackQuote:

Originally Posted by**pashah**

their domains are both the set of all real numbers.

Because these both represent parabolas which go to as

goes to , they can take all values greater than teir minimums.

The minimum of the first occurs when , which is at

, where , so for a. the range is .

The minimum of the second occurs when , which is at

, where , so for a. the range is .

RonL - August 3rd 2006, 07:30 AMThePerfectHackerQuote:

Originally Posted by**pashah**

Rewrite as,

Now, you need to find all such as this quadradic equation has a*real*solution. That happens when, the**discrimanant**is non-negative.

Simplify,

Thus,

Thus,

Quote:

b. y = 3x^2 + 2x +9

Work with discrimanant,