document.write( "Question 996072: Multiply 8(cos 35° + i sin 35°) and 8(cos 50° + i sin 50°). Can you please explain how to do this step by step? Thank You. \n" ); document.write( "

Algebra.Com's Answer #614644 by jim_thompson5910(35256) $\"\"$ $\"About$

You can put this solution on YOUR website!
Rule:
\n" ); document.write( "If
\n" ); document.write( "z1 = r1 * [ cos(theta1)+i*sin(theta1) ]
\n" ); document.write( "z2 = r2 * [ cos(theta2)+i*sin(theta2) ]
\n" ); document.write( "Then
\n" ); document.write( "z1*z2 = (r1*r2) * [ cos(theta1+theta2)+i*sin(theta1+theta2) ]\r
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\n" ); document.write( "\n" ); document.write( "In plain English:
\n" ); document.write( "multiply the r values out front; add the angles\r
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\n" ); document.write( "\n" ); document.write( "In this case,\r
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\n" ); document.write( "\n" ); document.write( "z1 = 8(cos 35° + i sin 35°)
\n" ); document.write( "z2 = 8(cos 50° + i sin 50°)\r
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\n" ); document.write( "\n" ); document.write( "Using the rule above, we get\r
\n" ); document.write( "\n" ); document.write( "z1*z2 = (8*8)* [ cos(35°+50°) + i*sin(35°+50°) ]
\n" ); document.write( "z1*z2 = 64 * [cos(85°) + i*sin(85°)]\r
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\n" ); document.write( "\n" ); document.write( "So the final answer is 64 * [cos(85°) + i*sin(85°)] \n" ); document.write( "

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