document.write( "Question 996088: Let g(x) = x |x + 5|\r
\n" ); document.write( "\n" ); document.write( "Find all critical numbers (if any) of g. Give answers in increasing order. Enter DNE in any unused space(s).\r
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\n" ); document.write( "\n" ); document.write( "Please help I dont understand the whole set up of absolute value. I had someone help solve and got.
\n" ); document.write( "g(x) = x|x+5|
\n" ); document.write( "|x+5| = (x+5) for x ≥ -5
\n" ); document.write( "|x+5| = -(x+5) for x < -5 \r
\n" ); document.write( "\n" ); document.write( "I don't understand this at all. Why is it ≥ or <\r
\n" ); document.write( "\n" ); document.write( "How is this solved..
\n" ); document.write( "So confused
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Algebra.Com's Answer #614652 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Rule: if y = |x|, then dy/dx = |x|/x\r
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\n" ); document.write( "\n" ); document.write( "Apply the derivative
\n" ); document.write( "g(x) = x*|x+5|
\n" ); document.write( "g ' (x) = |x+5| + x*(|x+5|)/(x+5) ... product rule (also use the rule above)
\n" ); document.write( "g ' (x) = |x+5| * [1 + x/(x+5)]
\n" ); document.write( "g ' (x) = |x+5| * [1*(x+5)/(x+5) + x/(x+5)]
\n" ); document.write( "g ' (x) = |x+5| * [(x+5)/(x+5) + x/(x+5)]
\n" ); document.write( "g ' (x) = |x+5| * [(x+5+x)/(x+5)]
\n" ); document.write( "g ' (x) = |x+5|*(2x+5)/(x+5)\r
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\n" ); document.write( "\n" ); document.write( "Solve g ' (x) = 0 for x to find the critical values
\n" ); document.write( "g ' (x) = |x+5|*(2x+5)/(x+5)
\n" ); document.write( "0 = |x+5|*(2x+5)/(x+5)
\n" ); document.write( "|x+5| = 0 or (2x+5)/(x+5) = 0
\n" ); document.write( "|x+5| = 0 or 2x+5 = 0\r
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\n" ); document.write( "\n" ); document.write( "If |x+5| = 0, then x+5 = 0 and x = -5
\n" ); document.write( "If 2x+5 = 0, then x = -5/2 = -2.5\r
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\n" ); document.write( "\n" ); document.write( "The critical numbers are -5 and -2.5
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