document.write( "Question 477546: What is the value of the expression 2(n upper) sigma 1(i lower bound) 3i=
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\n" ); document.write( "Can someone help me please? I do not \"get\" it! \n" ); document.write( "

Algebra.Com's Answer #327305 by Edwin McCravy(20056) $\"\"$ $\"About$

You can put this solution on YOUR website!
2(n upper) sigma 1(i lower bound) 3i=
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document.write( "I'm guessing that means this:\r\n" );
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document.write( ".  If not post again. \r\n" );
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document.write( "Then this means to plug in all the integers for i into 3i,\r\n" );
document.write( "starting with what i is equal to on the bottom and ending\r\n" );
document.write( "with i = whatever the value on the top is.  Then add up\r\n" );
document.write( "the results.\r\n" );
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document.write( "So, on the bottom we see that we start with i=1, so we\r\n" );
document.write( "substitute i=1 into 3i and get 3(1) or 3\r\n" );
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document.write( "The next integer after 1 is 2, so we substitute i=2 into\r\n" );
document.write( "3i and we get 3(2) = 6.\r\n" );
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document.write( "We've finished substituting because the number on the top\r\n" );
document.write( "is 2 and that means we stop already.  Usually there is \r\n" );
document.write( "bigger number than just 2 on top, but that's all there\r\n" );
document.write( "is here so we now add up what we've gotten:\r\n" );
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document.write( "3 + 6 = 9, so the correct answer is (b).\r\n" );
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document.write( "Edwin

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