document.write( "Question 988248: If f(x) = x + 5 and g(x) = 6x, then what is g(f)(x) -- that is, what is the value of the composite function, where we start with function f and end with function g -- if our starting input is 3? \n" ); document.write( "

Algebra.Com's Answer #608827 by vleith(2983) $\"\"$ $\"About$

You can put this solution on YOUR website!
To find g((f(x)) substitute the value for f(x) into g(x) everywhere\r
\n" ); document.write( "\n" ); document.write( "you are told f(x) = x+5\r
\n" ); document.write( "\n" ); document.write( "So substitute (x+5) for x everyplace it shows up in g(x)\r
\n" ); document.write( "\n" ); document.write( " $\"g%28x%29+=+6x\"$
\n" ); document.write( " $\"g%28f%28x%29%29+=+6%2A%28f%28x%29%29\"$
\n" ); document.write( " $\"+g%28f%28x%29%29+=+6%2A%28x%2B5%29\"$
\n" ); document.write( " $\"g%28f%28x%29%29+=+6x+%2B+30\"$ \r
\n" ); document.write( "\n" ); document.write( "Now it is easy to find g(f(x)) when x = 3. Just plug in 3 for x and simplify.\r
\n" ); document.write( "\n" ); document.write( "48 \n" ); document.write( "

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