document.write( "Question 267871: Prove by mathematical induction: ∑_(i=1)^n (3^i= 3(3^n-1)/2) \n" ); document.write( "

Algebra.Com's Answer #196786 by Edwin McCravy(20060) $\"\"$ $\"About$

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document.write( "It's true for n=1, because:\r\n" );
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document.write( "Assume true for any k such that \r\n" );
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document.write( "We want to prove that\r\n" );
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document.write( "Write that as the sum to k (for which we assume the formula holds,\r\n" );
document.write( "plus the (k+1)st term or \r\n" );
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document.write( "Edwin

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