document.write( "Question 708367: Please help me to understand the process of answering this question. I would really like to master this concept! :) Thank you in advance.\r
\n" ); document.write( "\n" ); document.write( "Let f(x) = x + 5 and g(x) = x^2. Find (g ° f) (4) \n" ); document.write( "

Algebra.Com's Answer #436090 by solver91311(24713) $\"\"$ $\"About$

You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "If

is a function defined by

, then if you are asked to evaluate

at some number, say, 2, which is to say evaluate

, you simply have to substitute 2 for every instance of

in the definition of

. That is:

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\n" ); document.write( "\n" ); document.write( "Likewise,

and

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\n" ); document.write( "\n" ); document.write( "Doing a composite,

is nothing more than evaluating the first function at the value of the second function, that is

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\n" ); document.write( "\n" ); document.write( "For your problem, you want

composite

, which is just

, or

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\n" ); document.write( "\n" ); document.write( "Whether or not your instructor expects you to expand the squared binomial is a matter between s/he and you. In any case, you still need to evaluate

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\n" ); document.write( "\n" ); document.write( "John
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\n" ); document.write( "Egw to Beta kai to Sigma
\n" ); document.write( "My calculator said it, I believe it, that settles it
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$\"The$

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