# Math Help - Domain of function

1. ## Domain of function

A) 1/(1-e^x)
B) sqrt(1-8^x)

2. Originally Posted by Asuhuman18
A) 1/(1-e^x)
B) sqrt(1-8^x)
A) $\frac{1}{1-e^x}$

The denominator must not equal zero, so $x \neq 0$.

B) $\sqrt{1-8^x}$

$1-8^x\geq0$

$1\geq8^x$

$x\leq0$

3. Originally Posted by alexmahone
A) $\frac{1}{1-e^x}$

The denominator must not equal zero, so $x \neq 1$. The domain is $R-{0}$.

== Most probably there's a little typo here: Alexmahone surely meant 1 - e^x =/= 0 and thus it must be x =/= 0, as he correctly wrote thereafter.

Tonio

B) $\sqrt{1-8^x}$

$1-8^x\geq0$

$1\geq8^x$

$x\leq0$
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