document.write( "Question 916916: Please check my work for the domain of:\r
\n" ); document.write( "\n" ); document.write( "f(x)=log_2(x+4)+log_2(x+6)\r
\n" ); document.write( "\n" ); document.write( "I set up a table of signs to solve this, please tell me if there is a better way to do this.\r
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document.write( "_____|-∞|-6|__|-4  |-∞ |\r\n" );
document.write( ".(x+4)|  -  | - | -  | o   | + |\r\n" );
document.write( "(x+6)| -   |o |+| +  | + |\r\n" );
document.write( "answ| +|X| - | 0   | + |\r\n" );
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\n" ); document.write( "\n" ); document.write( "therefore the domain is: (-∞,-4) U (-4,∞)\r
\n" ); document.write( "\n" ); document.write( "Is this correct?
\n" ); document.write( "Thank you \n" ); document.write( "
Algebra.Com's Answer #556404 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Values of x less than or equal to -4 will not work because x+4 will either be 0 or negative. Also, x+6 is likely to be negative as well.\r
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\n" ); document.write( "\n" ); document.write( "Keep in mind that the argument of a log, the stuff inside the log, must be positive.\r
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\n" ); document.write( "\n" ); document.write( "So (-∞,-4) is NOT part of the domain.\r
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\n" ); document.write( "\n" ); document.write( "The answer is simply (-4,∞) \n" ); document.write( "
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