document.write( "Question 1155428: Determine whether Rolle's theorem applies to the function shown below on the given interval. If so, find the point(s) that are guaranteed to exist by Rolle's theorem.
\n" ); document.write( "f(x)=x(x-8)^2; [0,8]
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Algebra.Com's Answer #778018 by MathLover1(20849)\"\" \"About 
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\n" ); document.write( "Rolle's Theorem
\n" ); document.write( "Let \"f\" be differentiable on the open interval (\"a\",\"b\") and continuous on the closed interval [\"a\",\"b\"].
\n" ); document.write( "Then if \"f%28a%29=f%28b%29\", then there is \"at\"\"+least\" one point \"c\" in (\"a\",\"b\") where \"f\"'\"%28c%29=0\".\r
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\n" ); document.write( "\n" ); document.write( "\"f%28x%29=x%28x-8%29%5E2\"; \r
\n" ); document.write( "\n" ); document.write( "[\"0\",\"8\"]=[\"a\",\"b\"]\r
\n" ); document.write( "\n" ); document.write( "check if \"f%28a%29=f%28b%29\" for\r
\n" ); document.write( "\n" ); document.write( "\"a=0\"
\n" ); document.write( "\"b=8\"\r
\n" ); document.write( "\n" ); document.write( "\"f%280%29=0%280-8%29%5E2=0\"
\n" ); document.write( "\"f%288%29=8%288-8%29%5E2=0\"\r
\n" ); document.write( "\n" ); document.write( "=> \"f%28a%29=f%28b%29\"\r
\n" ); document.write( "\n" ); document.write( "then derivate\r
\n" ); document.write( "\n" ); document.write( "\"f%28x%29=x%28x-8%29%5E2\"\r
\n" ); document.write( "\n" ); document.write( "apply the Product Rule : \"%28f%2Ag+%29\"'=\"f\"'*\"g\"+\"f\"* \"g\"'\r
\n" ); document.write( "\n" ); document.write( "\"f\"'\"%28x%29=%28d%2Fdx%29x%2A%28x-8%29%5E2%2Bx%2A%28d%2Fdx%29%28x-8%29%5E2\"\r
\n" ); document.write( "\n" ); document.write( "\"f\"'\"%28x%29=1%2A%28x-8%29%5E2%2Bx%2A2%28x-8%29\"\r
\n" ); document.write( "\n" ); document.write( "\"f\"'\"%28x%29=x%5E2-16x%2B64%2B2x%5E2-16x\"\r
\n" ); document.write( "\n" ); document.write( "\"f\"'\"%28x%29+=+3+x%5E2+-+32+x+%2B+64\"\r
\n" ); document.write( "\n" ); document.write( "find point \"c\" in (\"a\",\"b\") where \"f\"'\"%28c%29=0\"\r
\n" ); document.write( "\n" ); document.write( "\"+3x%5E2+-+32x+%2B+64=0\"\r
\n" ); document.write( "\n" ); document.write( " \"3x%5E2+-+24x-8x+%2B+64=0\"\r
\n" ); document.write( "\n" ); document.write( " \"%283+x%5E2+-+24x%29-%288x+-+64%29=0\"\r
\n" ); document.write( "\n" ); document.write( "\"%28x+-+8%29+%283x+-+8%29+=+0\"\r
\n" ); document.write( "\n" ); document.write( "solutions:\r
\n" ); document.write( "\n" ); document.write( "if \"%28x+-+8%29+=+0\"=>\"x=8\"
\n" ); document.write( "if \"+%283x+-+8%29+=+0\"=>\"x=8%2F3\"\r
\n" ); document.write( "\n" ); document.write( " the point(s) that are guaranteed to exist by Rolle's theorem are:\r
\n" ); document.write( "\n" ); document.write( "(\"8\",\"0\") and (\"8%2F3\",\"0\")\r
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