document.write( "Question 36340This question is from textbook Algebra and Trigonometry with Analytic Geometry
\n" ); document.write( ": I usually give the work that I've done to make sure I did it right, but in this case, I don't know where to begin. Here goes...\r
\n" ); document.write( "\n" ); document.write( "If f(x)=x^2 + 5, find f(a + h) - (a)\r
\n" ); document.write( "\n" ); document.write( "Thank you. \n" ); document.write( "
Algebra.Com's Answer #22269 by ilana(307)\"\" \"About 
You can put this solution on YOUR website!
Okay, this is just a confusing concept if you haven't had much exposure to it. Usually we see functions of the form f(x)=2x, or something like that. This is read \"f of x equals two x.\" So, in this case, if we were asked for f(a), we would say f(a)=2a, read \"f of a equals two a.\" Note, we simply plugged in the new value in parenthesis where the x was originally.
\n" ); document.write( "So in your question, let's take it in steps.
\n" ); document.write( "First, we can do the easiest part, f(a) (I'm guessing you meant f(a), not just (a)). f(a)=a^2+5.
\n" ); document.write( "Now, f(a+h)=(a+h)^2+5 = a^2+2ah+h^2+5.
\n" ); document.write( "Finally, subtracting the two gives:
\n" ); document.write( "f(a+h)-f(a) = (a^2+2ah+h^2+5)-(a^2+5) = a^2+2ah+h^2+5-a^2-5 = 2ah+h^2
\n" ); document.write( "So the answer is 2ah+h^2.\r
\n" ); document.write( "\n" ); document.write( "(If it was really (a), not f(a), it would jsut be (a^2+2ah+h^2+5)-(a) = a^2+2ah+h^2+5-a.)\r
\n" ); document.write( "\n" ); document.write( "Just by the way, this is the beginning of calculus:). \n" ); document.write( "
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