document.write( "Question 1200073: By using the Intermediate Value Theorem, show that the equation: nth root of x = 1-x has at least one solution in the open interval (0,1) for any positive integer n>=3. \r
\n" ); document.write( "\n" ); document.write( ">= means greater than or equal to
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Algebra.Com's Answer #834091 by math_tutor2020(3817)\"\" \"About 
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\n" ); document.write( "\"root%28n%2Cx%29+=+1-x\"\r
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\n" ); document.write( "\n" ); document.write( "\"root%28n%2Cx%29-1%2Bx+=+0\"\r
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\n" ); document.write( "\n" ); document.write( "\"f%28x%29+=+0\"\r
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\n" ); document.write( "\n" ); document.write( "The left hand side is the function \"f%28x%29+=+root%28n%2Cx%29-1%2Bx\"\r
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\n" ); document.write( "\n" ); document.write( "Plug in x = 0
\n" ); document.write( "\"f%28x%29+=+root%28n%2Cx%29-1%2Bx\"\r
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\n" ); document.write( "\n" ); document.write( "\"f%280%29+=+root%28n%2C0%29-1%2B0\"\r
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\n" ); document.write( "\n" ); document.write( "\"f%280%29+=+0-1%2B0\"\r
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\n" ); document.write( "\n" ); document.write( "\"f%280%29+=+-1\"
\n" ); document.write( "The result is negative.\r
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\n" ); document.write( "\n" ); document.write( "Plug in x = 1
\n" ); document.write( "\"f%28x%29+=+root%28n%2Cx%29-1%2Bx\"\r
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\n" ); document.write( "\n" ); document.write( "\"f%281%29+=+root%28n%2C1%29-1%2B1\"\r
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\n" ); document.write( "\n" ); document.write( "\"f%281%29+=+1-1%2B1\"\r
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\n" ); document.write( "\n" ); document.write( "\"f%281%29+=+1\"
\n" ); document.write( "The result is positive.\r
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\n" ); document.write( "\n" ); document.write( "f(x) changes from negative to positive when going through this interval 0 < x < 1.
\n" ); document.write( "Somewhere in the middle we must have f(x) = 0 occur at least once, which leads to f(x) having at least one root in this interval.
\n" ); document.write( "This is because f(x) is a continuous curve.\r
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\n" ); document.write( "\n" ); document.write( "Identities used:
\n" ); document.write( "\"root%28n%2C0%29+=+0\"
\n" ); document.write( "\"root%28n%2C1%29+=+1\"
\n" ); document.write( "Those two identities are based on
\n" ); document.write( "\"0%5En+=+0\" where n > 0
\n" ); document.write( "\"1%5En+=+1\"
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