document.write( "Question 61330: I seem to be having a small problem understanding Binomial Theorems as far as substitution and Expansion. Your assistancewith this problem would be greatly appreciated:\r
\n" ); document.write( "\n" ); document.write( "It states: Use substitution to find the expansion of (c-2i)^5. Simplify your final result.\r
\n" ); document.write( "\n" ); document.write( "Please help!
\n" ); document.write( "Thanks in advance!
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Algebra.Com's Answer #42212 by Cintchr(481)\"\" \"About 
You can put this solution on YOUR website!
\"+%28c-2i%29%5E5+\"
\n" ); document.write( "let's expand this out
\n" ); document.write( "\"+%28c-2i%29%28c-2i%29%28c-2i%29%28c-2i%29%28c-2i%29+\"
\n" ); document.write( "Looking at just the first 2 quantities ... let's FOIL them
\n" ); document.write( "F: \"+c+%2A+c+=+c%5E2+\"
\n" ); document.write( "O: \"+c+%2A+-2i+=+-2ci+\"
\n" ); document.write( "I: \"+-2i+%2A+c+=+-2ci+\"
\n" ); document.write( "L: \"+-2i+%2A+-2i+=+4i%5E2+=4%28-1%29+=+-4+\"
\n" ); document.write( "remember i^2 = -1
\n" ); document.write( "Combine like terms
\n" ); document.write( "\"+c%5E2+-4ci+-4+\"
\n" ); document.write( "Now the 3rd and 4th terms when FOILed, give the same response.
\n" ); document.write( "You now have the following
\n" ); document.write( "\"+%28c%5E2+-4ci+-4%29%28c%5E2+-4ci+-4%29%28c-2i%29+\"
\n" ); document.write( "now multiply out the two trinomials
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\n" ); document.write( "simplify
\n" ); document.write( "\"+c%5E4+-4c%5E3i+-4c%5E2+-4c%5E3i+-16c%5E2i%5E2+%2B16ci+-4c%5E2+%2B16ci+%2B16+\"
\n" ); document.write( "multiply, working the i^2 as well
\n" ); document.write( "\"+c%5E4+-8c%5E3i+-8c%5E2+-16c%5E2%28-1%29+%2B16ci+%2B16+\"
\n" ); document.write( "combine like terms
\n" ); document.write( "\"+c%5E4+-+8c%5E3i+-8c%5E2+%2B16c%5E2+%2B16ci+%2B16+\"
\n" ); document.write( "\"+c%5E4+-+8c%5E3i+%2B8c%5E2+%2B16ci+%2B16+\"
\n" ); document.write( "Now using this quantity ... multiply it by the 5th (c-2i)
\n" ); document.write( "\"+%28c-2i%29%28c%5E4+-8c%5E3i+%2B8c%5E2+%2B16ci+%2B16%29+\"
\n" ); document.write( "
\n" ); document.write( "Multiply, working the i^2 as well
\n" ); document.write( "
\n" ); document.write( "combine like terms
\n" ); document.write( "\"+c%5E5+-10c%5E4i+-+8c%5E3i+%2B+48c+-+32i+\"
\n" ); document.write( "the c^2 cancel out\r
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