document.write( "Question 202032: Find the domain of f(x)=sqrt x-4. thanks\r
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Algebra.Com's Answer #152290 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"sqrt%28x-4%29\" Start with the given expression\r
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\n" ); document.write( "\n" ); document.write( "Remember you cannot take the square root of a negative value. So that means the argument \"x-4\" must be greater than or equal to zero (i.e. the argument must be non-negative)\r
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\n" ); document.write( "\n" ); document.write( "\"x-4%3E=0\" Set the inner expression greater than or equal to zero\r
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\n" ); document.write( "\n" ); document.write( "\"x%3E=0%2B4\"Add 4 to both sides\r
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\n" ); document.write( "\n" ); document.write( "\"x%3E=4\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "So that means x must be greater than or equal to \"4\" in order for x to be in the domain\r
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\n" ); document.write( "\n" ); document.write( "So the domain in set-builder notation is\r
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\n" ); document.write( "\n" ); document.write( "So here is the domain in interval notation: [4,)\r
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\n" ); document.write( "\n" ); document.write( "Notice if we graph \"y=sqrt%28x-4%29\" , we get\r
\n" ); document.write( "\n" ); document.write( "\"+graph%28+500%2C+500%2C+-10%2C+10%2C+-10%2C+10%2C+sqrt%28x-4%29%29+\" notice how the graph never crosses the line \"x=4\". So this graphically verifies our answer.\r
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\n" ); document.write( "\n" ); document.write( "and we can see that x must be greater than or equal to \"4\" in order to lie on the graph
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