2 Attachment(s)
Range and Domain of Functions
Find the Domain of
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I can do this Question using graphs. I need help in doing it without graphs ... some help please
Find the Domain of
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$\displaystyle -1 <= [2x^2 - 3] <= 1$
$\displaystyle -1 <= (2x^2 - 3) < 2$
$\displaystyle 1 <= x^2 < \frac{5}{2}$
Why?
$\displaystyle |x| >= 1$ and $\displaystyle |x| < \sqrt{\frac{5}{2}}$
$\displaystyle x \in (-\sqrt{\frac{5}{2}},-1]\cup[1,\sqrt{\frac{5}{2}})$
but the answer is
$\displaystyle x \in [-\sqrt{\frac{5}{2}},-1]\cup[1,\sqrt{\frac{5}{2}}]$
Why is the 5/2 terms included?