document.write( "Question 955784: if one root of the equation (p^2+2)x^2+7x+3p=0 is the reciprocal of the another then find the value of p
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Algebra.Com's Answer #583884 by MathLover1(20849)\"\" \"About 
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Let \"r\" be one root. Then the other root will be \"1%2Fr\". Consequently, their product will be \"%28r%29%2A%281%2Fr%29+=+1\". This is true if \"r\" is nonzero.\r
\n" ); document.write( "\n" ); document.write( "Now, let \"f%28x%29+=+%28p%5E2%2B2%29x%5E2%2B7x%2B3p=+ax%5E2+%2B+bx+%2B+c\". => \"a=%28p%5E2%2B2%29\" ,\"b=7\",\"+c=3p\"
\n" ); document.write( "If \"f%28x%29+=+0\", then we are given that the roots are \"r\" and \"1%2Fr\".
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\n" ); document.write( "since product of roots is \"+c%2Fa=1\", we have\r
\n" ); document.write( "\n" ); document.write( "=>\"c%2Fa=3p%2F%28p%5E2%2B2%29=1\"\r
\n" ); document.write( "\n" ); document.write( "\"3p=1%2A%28p%5E2%2B2%29\"\r
\n" ); document.write( "\n" ); document.write( "\"0=p%5E2-3p%2B2\"\r
\n" ); document.write( "\n" ); document.write( "\"0=p%5E2-2p-p%2B2\"\r
\n" ); document.write( "\n" ); document.write( "\"0=%28p%5E2-2p%29-%28p-2%29\"
\n" ); document.write( "\"0=p%28p-2%29-%28p-2%29\"
\n" ); document.write( "\"0=%28p-1%29%28p-2%29\"\r
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\n" ); document.write( "\n" ); document.write( "=> \"highlight%28p=1%29+\" or
\n" ); document.write( "=> \"highlight%28p=2%29+\"\r
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\n" ); document.write( "\n" ); document.write( "since SUM OF THE ROOTS is\r
\n" ); document.write( "\n" ); document.write( "\"+r+%2B+1%2Fr+=+-b%2Fa\"\r
\n" ); document.write( "\n" ); document.write( "\"+r+%2B+1%2Fr+=+-7%2F%28p%5E2%2B2%29\"\r
\n" ); document.write( "\n" ); document.write( "Computing for \"r\": \r
\n" ); document.write( "\n" ); document.write( "if \"highlight%28p=1%29+\"\r
\n" ); document.write( "\n" ); document.write( "\"+r+%2B+1%2Fr+=+-7%2F%281%5E2%2B2%29\"\r
\n" ); document.write( "\n" ); document.write( "\"+%28r%5E2+%2B+1%29%2Fr+=+-7%2F3\"\r
\n" ); document.write( "\n" ); document.write( "\"+3%28r%5E2+%2B+1%29+=+-7r\"\r
\n" ); document.write( "\n" ); document.write( "\"+3r%5E2+%2B+3=+-7r\"\r
\n" ); document.write( "\n" ); document.write( "\"+3r%5E2+%2B7r%2B+3=+0\"\r
\n" ); document.write( "\n" ); document.write( "\"r+=+%281%2F6%29+%28sqrt%2813%29-7%29\" or \"r+=+%281%2F6%29+%28-7-sqrt%2813%29%29\"\r
\n" ); document.write( "\n" ); document.write( "where \"%281%2F6%29+%28sqrt%2813%29-7%29+=+1%2F%28%281%2F6%29+%28-7-sqrt%2813%29%29%29\"-roots are reciprocal to each other\r
\n" ); document.write( "\n" ); document.write( "Thus, the actual roots are:\r
\n" ); document.write( "\n" ); document.write( " \"r%5B1+%5D=+%281%2F6%29+%28sqrt%2813%29-7%29+\" or
\n" ); document.write( "\"r%5B2+%5D=+%281%2F6+%29%28-7-sqrt%2813%29%29\"\r
\n" ); document.write( "\n" ); document.write( "second solution:\r
\n" ); document.write( "\n" ); document.write( "if \"highlight%28p=2%29+\"\r
\n" ); document.write( "\n" ); document.write( "\"+r+%2B+1%2Fr+=+-7%2F%282%5E2%2B2%29\"\r
\n" ); document.write( "\n" ); document.write( "\"+%28r%5E2+%2B+1%29%2Fr+=+-7%2F6\"\r
\n" ); document.write( "\n" ); document.write( "\"+6%28r%5E2+%2B+1%29+=+-7r\"\r
\n" ); document.write( "\n" ); document.write( "\"+6r%5E2+%2B+6=+-7r\"\r
\n" ); document.write( "\n" ); document.write( "\"+6r%5E2+%2B7r%2B+6=+0\"...solving this using quadratic formula you will get\r
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\n" ); document.write( "\n" ); document.write( "\"r+%5B1%5D=+-%281%2F12%29%2Ai%28sqrt%2895%29-7i%29\" or \"r%5B2%5D+=+%281%2F12%29%2Ai+%28sqrt%2895%29%2B7i%29\"\r
\n" ); document.write( "\n" ); document.write( "where \"r+%5B1%5D=1%2Fr+%5B2%5D\"=> \"-%281%2F12%29%2Ai+%28sqrt%2895%29-7i%29=1%2F%28%281%2F12%29%2Ai+%28sqrt%2895%29%2B7i%29%29+\"\r
\n" ); document.write( "\n" ); document.write( "check our function: if \"highlight%28p=1%29+\"\r
\n" ); document.write( "\n" ); document.write( "\"%28p%5E2%2B2%29x%5E2%2B7x%2B3p=0\"
\n" ); document.write( "\"%281%5E2%2B2%29x%5E2%2B7x%2B3%2A1=0\"
\n" ); document.write( "\"3x%5E2%2B7x%2B3=0\"\r
\n" ); document.write( "\n" ); document.write( "roots are: \"x+=+%281%2F6%29+%28sqrt%2813%29-7%29\" or \"x+=+%281%2F6%29+%28-7-sqrt%2813%29%29\" which are reciprocal to each other\r
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\n" ); document.write( "\n" ); document.write( "and, if \"highlight%28p=2%29+\"\r
\n" ); document.write( "\n" ); document.write( "\"%28p%5E2%2B2%29x%5E2%2B7x%2B3p=0\"
\n" ); document.write( "\"%282%5E2%2B2%29x%5E2%2B7x%2B3%2A2=0\"
\n" ); document.write( "\"6x%5E2%2B7x%2B6=0\"\r
\n" ); document.write( "\n" ); document.write( "roots are: => \"x=-%281%2F12%29%2Ai+%28sqrt%2895%29-7i%29\" or \"x=%28%281%2F12%29%2Ai+%28sqrt%2895%29%2B7i%29%29+\" and they are reciprocal to each other\r
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