Calculus
Methods
01
Finding Domains
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1) Rewrite function as a single fraction, and factor the
denominator.
2) There are only three rules:
A) No negative numbers are allowed inside square roots.
B) No zeroes are allowed in the denominator.
C) No non-positive numbers are allowed inside logs.
3) Write separate domains for each item involved in the
function.
4) Combine the separate domains using "and."
Example: Find the domain of
1)
2A) There is only one square root (it occurs twice):
2B) There are two factors in the denominator:
2C) There is one logarithm:
3) The four domains for this example problem are thus:
4) The single domain that is commensurate with all of
the above domains is (it might help to draw a number
line):
Domain:
Or in interval notation:
On to Method 02 - Solving Polynomial Inequalities