document.write( "Question 153021: Find the Inverse of \"+f%28x%29=3%2Bx%5E3+\"\r
\n" ); document.write( "\n" ); document.write( "Use Descarte's Rule of Signes to determine the number of positive and negative real zeros of the polynomial \"+p%28x%29+=+2x%5E4%2B3x%5E3-2x%5E2%2Bx-2+\" can have\r
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Algebra.Com's Answer #112472 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
# 1)\r
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\n" ); document.write( "\n" ); document.write( "\"y=3%2Bx%5E3\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"x=3%2By%5E3\" Switch x and y\r
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\n" ); document.write( "\n" ); document.write( "\"x-3=y%5E3\" Subtract 3 from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"root%283%2Cx-3%29=y\" Subtract 3 from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"y=root%283%2Cx-3%29\"\r
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\n" ); document.write( "\n" ); document.write( "So the inverse function is \r
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\n" ); document.write( "\n" ); document.write( "# 2)\r
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Positive Zeros:

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\n" ); document.write( "\n" ); document.write( "First count the sign changes of \"f%28x%29=2x%5E4%2B3x%5E3-2x%5E2%2Bx-2\"\r
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\n" ); document.write( "\n" ); document.write( "From \"2x%5E4\" to \"3x%5E3\", there is no change in sign\r
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\n" ); document.write( "\n" ); document.write( "From \"3x%5E3\" to \"-2x%5E2\", there is a sign change from positive to negative \r
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\n" ); document.write( "\n" ); document.write( "From \"-2x%5E2\" to \"x\", there is a sign change from negative to positive \r
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\n" ); document.write( "\n" ); document.write( "From \"x\" to \"-2\", there is a sign change from positive to negative \r
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\n" ); document.write( "\n" ); document.write( "So there are 3 sign changes for the expression \"f%28x%29=2x%5E4%2B3x%5E3-2x%5E2%2Bx-2\". \r
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\n" ); document.write( "\n" ); document.write( "So there are 3 or 1 positive zeros\r
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Negative Zeros:

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\n" ); document.write( "\n" ); document.write( "\"f%28-x%29=2%28-x%29%5E4%2B3%28-x%29%5E3-2%28-x%29%5E2%2B%28-x%29-2\" Now let's replace each \"x\" with \"-x\"\r
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\n" ); document.write( "\n" ); document.write( "\"f%28-x%29=2x%5E4-3x%5E3-2x%5E2-x-2\" Simplify\r
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\n" ); document.write( "\n" ); document.write( "Now let's count the sign changes of \"f%28-x%29=2x%5E4-3x%5E3-2x%5E2-x-2\"\r
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\n" ); document.write( "\n" ); document.write( "From \"2x%5E4\" to \"-3x%5E3\", there is a sign change from positive to negative \r
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\n" ); document.write( "\n" ); document.write( "From \"-3x%5E3\" to \"-2x%5E2\", there is no change in sign\r
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\n" ); document.write( "\n" ); document.write( "From \"-2x%5E2\" to \"-x\", there is no change in sign\r
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\n" ); document.write( "\n" ); document.write( "From \"-x\" to \"-2\", there is no change in sign\r
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\n" ); document.write( "\n" ); document.write( "So there is 1 sign change for the expression \"f%28-x%29=2x%5E4-3x%5E3-2x%5E2-x-2\". \r
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\n" ); document.write( "\n" ); document.write( "So there is 1 negative zero
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