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x^2 + 2x-3 should be greater than 0 since (Any number)/0 is NOt DefinedQuote:
I need to determine the domain, sketch the graph of each function and show/explain the connection between the graph and the domain:
g (x) = x^2
______________
x^2 + 2x - 3
(X+3)(X-1)>0
So either
X> -3 OR X>1
Thus domain becomes
(-3,1)u(1,Infinity)
Right?
Now how wld I graph and explain the connection??
The values of x such thatQuote:
Originally Posted by askmemath
are forbidden. NOT where
is negative. There are three parts to the domain.
Wherever the denominator goes to zero will be a vertical asymptote (unless the numerator also goes to zero at this value of x, which does not happen here).
-Dan
Umm, So the domain becomes....??Quote:
Originally Posted by topsquarkThe values of x such that
Wherever the denominator goes to zero will be a vertical asymptote (unless the numerator also goes to zero at this value of x, which does not happen here).
-Dan
And how would I be graphing this?
The domain is that "x" can be any number EXCEPTQuote:
Originally Posted by askmemath
.
You can write it in three ways,
Or,
Or,
Step 1 draw vertical line which are asymptotes for the undefinied values. That means drawQuote:
Originally Posted by askmemath
Step 2 find how f(x) behaves as you approach one of these values from the left and right. Meaning, begin with the vertical asymptotes x=-3 first. As you approach the number -3 from the left what happens to f(x)? It gets bigger and bigger. That means it is approaching +infinity so you approach the asymptote line but you never pass it. Next what happens when you approach x=-3 from the left? It gets smaller and smaller. That means it is approaching -infinity so you approach the asymptote line but you never pass it and go down. The same approach use for x=1.