document.write( "Question 1160095: (a) Let f(x)= sqrt(9+6x^2) Find f ' (x)
\n" ); document.write( "(b) Let f(x)= e^sqrt(9+6x^2) Find f ' (x)
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Algebra.Com's Answer #783252 by MathLover1(20850)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( "Let \"f%28x%29=+sqrt%289%2B6x%5E2%29\" \r
\n" ); document.write( "\n" ); document.write( "Find \"f\" ' \"%28x%29\":\r
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\n" ); document.write( "\n" ); document.write( "apply the chain rule:\"%28df%2Au%29%2F%28dx%29=%28df%2Fdu%29%28du%2Fdx%29\"\r
\n" ); document.write( "\n" ); document.write( "\"f=sqrt%28u%29\", \"u=9%2B6x%5E2\"\r
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\n" ); document.write( "\n" ); document.write( " \"f\"'\"%28x%29=%28d%2Fdu%29%28u%29+%2A%28d%2Fdx%29%289%2B6x%5E2%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28d%2Fdu%29%28u%29=1%2F%282sqrt%28u%29%29\"\r
\n" ); document.write( "\n" ); document.write( "\"%28d%2Fdx%29%289%2B6x%5E2%29=12x\"\r
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\n" ); document.write( "\n" ); document.write( "\"f\"'\"%28x%29=%281%2F%282sqrt%28u%29%29%29%2A12x\"\r
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\n" ); document.write( "\n" ); document.write( "substitute back \"u=9%2B6x%5E2\"\r
\n" ); document.write( "\n" ); document.write( "\"f+\"' \"%28x%29=%281%2F%282sqrt%289%2B6x%5E2%29%29%29%2A12x\"\r
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\n" ); document.write( "\n" ); document.write( "\"f\"'\"%28x%29=12x%2F%282sqrt%289%2B6x%5E2%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"f\"'\"%28x%29=6x%2F%28sqrt%289%2B6x%5E2%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "(b) \r
\n" ); document.write( "\n" ); document.write( "Let \"f%28x%29=+e%5Esqrt%289%2B6x%5E2%29+\"\r
\n" ); document.write( "\n" ); document.write( "Find \"f\"'\"%28x%29\"\r
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\n" ); document.write( "\n" ); document.write( "apply the chain rule:\"%28df%2Au%29%2F%28dx%29=%28df%2Fdu%29%28du%2Fdx%29\"\r
\n" ); document.write( "\n" ); document.write( "\"f=e%5Eu\", \"u=sqrt%289%2B6x%5E2%29\"\r
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\n" ); document.write( "\"f\"'\"%28x%29=%28d%2Fdu%29%28e%5Eu%29+%2A%28d%2Fdx%29%28sqrt%289%2B6x%5E2%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28d%2Fdu%29%28e%5Eu%29+=e%5Eu\"\r
\n" ); document.write( "\n" ); document.write( "\"%28d%2Fdx%29%28sqrt%289%2B6x%5E2%29%29=6x%2Fsqrt%289%2B6x%5E2%29\"\r
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\n" ); document.write( "\n" ); document.write( " \"f\"' \"%28x%29=e%5Eu%2A%286x%2Fsqrt%289%2B6x%5E2%29%29\"..........substitute back \"u=sqrt%289%2B6x%5E2%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"f\"'\r
\n" ); document.write( "\n" ); document.write( "\"f\"'\r
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