How do you find the domain and range of log_(6) (49-x^2)?

1 Answer
May 30, 2017

The argument of a log function must be positive.

Explanation:

So
49-x^2>0->x^2<49

This only happens if
-7 < x<+7 this is the domain

Range:
With x nearing +-7 the argument 49-x^2 will be nearing 0 and the log itself will go to -oo

Or, in the language:
lim_(x->+-7) log_6 (49-x^2)=-oo

The top of the range is when the argument is maximal, this means when x=0, the max value will be:
log_6 49=log_10 49/log_10 6~~2.172
graph{log(49-x^2)/log(6) [-12.33, 12.99, -7.11, 5.55]}