document.write( "Question 1206122: If a+1/3a=2 then find the value of 9a^2+1/a^2 \n" ); document.write( "
Algebra.Com's Answer #843363 by math_tutor2020(3817)\"\" \"About 
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\n" ); document.write( "I'll assume the given equation is \"a+%2B+1%2F%283a%29+=+2\"
\n" ); document.write( "And I'll assume you want to find the value of \"9a%5E2+%2B+1%2F%28a%5E2%29\"
\n" ); document.write( "Please let me know if otherwise.\r
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\n" ); document.write( "\n" ); document.write( "If my assumptions are correct, then you should be careful to use parenthesis.
\n" ); document.write( "Something like a + 1/3a could be misinterpreted as \"a%2B%281%2F3%29a\"
\n" ); document.write( "So instead of a + 1/3a, you should type in a + 1/(3a)
\n" ); document.write( "Instead of 9a^2+1/a^2, you should type in 9a^2+1/(a^2)\r
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\n" ); document.write( "\n" ); document.write( "The original equation just involves 'a' without any exponent.
\n" ); document.write( "The thing we want to find has 'a' being squared.
\n" ); document.write( "A naive approach could be to simply square both sides to see what happens.\r
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\n" ); document.write( "\n" ); document.write( "\"a+%2B+1%2F%283a%29+=+2\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28a+%2B+1%2F%283a%29%29%5E2+=+2%5E2\"\r
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\n" ); document.write( "\n" ); document.write( "\"a%5E2+%2B+2%2Aa%2A%281%2F%283a%29%29+%2B+%281%2F%283a%29%29%5E2+=+4\" Use formula (p+q)^2 = p^2+2pq+q^2\r
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\n" ); document.write( "\n" ); document.write( "\"a%5E2+%2B+2%2F3+%2B+1%2F%289a%5E2%29+=+4\" The 'a's cancel out in the middle portion.\r
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\n" ); document.write( "\n" ); document.write( "\"a%5E2+%2B+1%2F%289a%5E2%29+=+4+-+2%2F3\" \r
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\n" ); document.write( "\n" ); document.write( "\"a%5E2+%2B+1%2F%289a%5E2%29+=+10%2F3\" \r
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\n" ); document.write( "\n" ); document.write( "We want to find \"9a%5E2+%2B+1%2F%28a%5E2%29\", but we have \"a%5E2+%2B+1%2F%289a%5E2%29\" on the left hand side.
\n" ); document.write( "The coefficients for the a^2 terms (1 and 9) have been swapped.
\n" ); document.write( "A quick easy fix is to multiply both sides by 9.\r
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\n" ); document.write( "\n" ); document.write( "\"a%5E2+%2B+1%2F%289a%5E2%29+=+10%2F3\" \r
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\n" ); document.write( "\n" ); document.write( "\"9%2A%28a%5E2+%2B+1%2F%289a%5E2%29%29+=+9%2A10%2F3\" \r
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\n" ); document.write( "\n" ); document.write( "\"9a%5E2+%2B+9%2A%281%2F%289a%5E2%29%29+=+90%2F3\" \r
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\n" ); document.write( "\n" ); document.write( "\"9a%5E2+%2B+1%2F%28a%5E2%29+=+30\" \r
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\n" ); document.write( "\n" ); document.write( "Answer: 30
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