document.write( "Question 1082385: How I can solve this equation
\n" ); document.write( "If g(x).f(x)= 4 ; at x=4 , g(4)=2 , g'(4) = 1/4 ; calculate f'(4) ??? \n" ); document.write( "

Algebra.Com's Answer #696454 by Fombitz(32388) $\"\"$ $\"About$

You can put this solution on YOUR website!
At $\"x=4\"$ ,
\n" ); document.write( " $\"g%284%29f%284%29=4\"$
\n" ); document.write( " $\"2%2Af%284%29=4\"$
\n" ); document.write( " $\"f%284%29=2\"$
\n" ); document.write( "and
\n" ); document.write( " $\"gf=4\"$
\n" ); document.write( "Differentiating implicitly,
\n" ); document.write( " $\"g%2A%28df%2Fdx%29%2Bf%2A%28dg%2Fdx%29=0\"$
\n" ); document.write( "So at $\"x=4\"$ ,
\n" ); document.write( " $\"2%2A%28df%2Fdx%29%2B2%2A%281%2F4%29=0\"$
\n" ); document.write( " $\"2%2A%28df%2Fdx%29=-1%2F2\"$
\n" ); document.write( " $\"df%2Fdx=-1%2F4\"$
\n" ); document.write( " \n" ); document.write( "

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