document.write( "Question 1203773: f(x) = x^2 + 5\r
\n" ); document.write( "\n" ); document.write( "a) f(-6) =\r
\n" ); document.write( "\n" ); document.write( "b) Find if f(x) = 14\r
\n" ); document.write( "\n" ); document.write( "c) f(x + h) =\r
\n" ); document.write( "\n" ); document.write( "d) Calculate: f(x + h) - f(x) over h\r
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\n" ); document.write( "\n" ); document.write( "Can you please explain to me this homework question by showing the step-by-step calculations? Thank you!
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Algebra.Com's Answer #839603 by Theo(13342)\"\" \"About 
You can put this solution on YOUR website!
f(x) = x^2 + 5\r
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\n" ); document.write( "\n" ); document.write( "a.
\n" ); document.write( "f(-6) = (-6)^2 + 5 = 36 + 5 = 41.
\n" ); document.write( "x is replaced by -6.\r
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\n" ); document.write( "\n" ); document.write( "b.
\n" ); document.write( "f(x) = 14.
\n" ); document.write( "this means that x^2 + 5 = 14
\n" ); document.write( "subtract 5 from both sides of the equation to get x^2 = 9.
\n" ); document.write( "solve for x to get x = 3
\n" ); document.write( "f(3) = 3^2 + 5 = 14.\r
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\n" ); document.write( "\n" ); document.write( "c.
\n" ); document.write( "f(x) = x^2 + 5
\n" ); document.write( "f(x+h) = (x+h)^2 + 5
\n" ); document.write( "you are replacing (x) with (x+h)
\n" ); document.write( "f(x+h) = (x+h)^2 + 5 = x^2 + 2hx + h^2 + 5\r
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\n" ); document.write( "\n" ); document.write( "d.
\n" ); document.write( "Calculate: f(x + h) - f(x) over h
\n" ); document.write( "from (c), you have f(x+h) = x^2 + 2hx + h^2 + 5
\n" ); document.write( "subtract f(x) from that and divide by h to get:
\n" ); document.write( "(f(x+h) - f(x)) / h = (x^2 + 2hx + 5 + h^2 - x^2 - 5) / h
\n" ); document.write( "simplify to get (2hx + h^2) / h
\n" ); document.write( "simplify further to get 2x + h.\r
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\n" ); document.write( "\n" ); document.write( "this might be easier to see in the attached worksheet.\r
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\n" ); document.write( "\n" ); document.write( "the limit as h approaches 0 becomes 2x.
\n" ); document.write( "this is the derivative of x^2 + 5.
\n" ); document.write( "you will learn this later, if you haven't already.
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