document.write( "Question 1040330: F(x+h)-f(x)/h where f(x)=x^2-x+4 \n" ); document.write( "
Algebra.Com's Answer #655131 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Let's start by computing f(x+h)\r
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\n" ); document.write( "\n" ); document.write( "f(x) = x^2 - x + 4
\n" ); document.write( "f(x+h) = (x+h)^2 - (x+h) + 4 ... replace every 'x' with (x+h)
\n" ); document.write( "f(x+h) = (x^2+2xh+h^2) - (x+h) + 4
\n" ); document.write( "f(x+h) = x^2+2xh+h^2 - x-h + 4\r
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\n" ); document.write( "\n" ); document.write( "So \"f%28x%2Bh%29+=+x%5E2%2B2xh%2Bh%5E2+-+x-h+%2B+4\"\r
\n" ); document.write( "\n" ); document.write( "----------------------------\r
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\n" ); document.write( "\n" ); document.write( "Using what we found earlier, let's subtract f(x) from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"f%28x%2Bh%29+=+x%5E2%2B2xh%2Bh%5E2+-+x-h+%2B+4\"
\n" ); document.write( "\"f%28x%2Bh%29-f%28x%29+=+x%5E2%2B2xh%2Bh%5E2+-+x-h+%2B+4-f%28x%29\"
\n" ); document.write( "\"f%28x%2Bh%29-f%28x%29+=+x%5E2%2B2xh%2Bh%5E2+-+x-h+%2B+4-%28f%28x%29%29\"
\n" ); document.write( "\"f%28x%2Bh%29-f%28x%29+=+x%5E2%2B2xh%2Bh%5E2+-+x-h+%2B+4-%28x%5E2-x%2B4%29\" Replace f(x) with x^2-x+4
\n" ); document.write( "\"f%28x%2Bh%29-f%28x%29+=+x%5E2%2B2xh%2Bh%5E2+-+x-h+%2B+4-x%5E2%2Bx-4\"
\n" ); document.write( "\"f%28x%2Bh%29-f%28x%29+=+2xh%2Bh%5E2-h\"\r
\n" ); document.write( "\n" ); document.write( "----------------------------
\n" ); document.write( "Now that's divide that by h\r
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\n" ); document.write( "\n" ); document.write( "\"f%28x%2Bh%29-f%28x%29+=+2xh%2Bh%5E2-h\"
\n" ); document.write( "\"%28f%28x%2Bh%29-f%28x%29%29%2Fh+=+%282xh%2Bh%5E2-h%29%2Fh\"
\n" ); document.write( "\"%28f%28x%2Bh%29-f%28x%29%29%2Fh+=+%28h%282x%2Bh-1%29%29%2Fh\"
\n" ); document.write( "\"%28f%28x%2Bh%29-f%28x%29%29%2Fh+=+2x%2Bh-1\"
\n" ); document.write( "----------------------------\r
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\n" ); document.write( "\n" ); document.write( "So in the end, after simplifying, \"%28f%28x%2Bh%29-f%28x%29%29%2Fh\" is equal to \"2x%2Bh-1\"
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