document.write( "Question 1032622: Let z = 12 (cos 7π/6 + i sin 7π/6) and w = 6 (cos π/3 + i sin π/3). Write the rectangular form of zw.\r
\n" ); document.write( "\n" ); document.write( "A. 72 + 72i
\n" ); document.write( "B. -72i
\n" ); document.write( "C. -18 - 18√3 i
\n" ); document.write( "D. 18 + 18√3 i
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Algebra.Com's Answer #647282 by Alan3354(69443)\"\" \"About 
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Let z = 12 (cos 7π/6 + i sin 7π/6) and w = 6 (cos π/3 + i sin π/3). Write the rectangular form of zw.
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\n" ); document.write( "Let z = 12cis(7pi/6) and w = 6cis(pi/3). Write the rectangular form of zw.
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\n" ); document.write( "zw = 12*6cis(7pi/6 + pi/3) = 72cis(3pi/2) = 72*cos(3pi/2) = 72i*sin(3pi/2)
\n" ); document.write( "= -72i
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