How do you multiply e7π12eπ2i in trigonometric form?

1 Answer
Nov 22, 2017

The answer is =2+64+264i

Explanation:

Apply Euler's relation

eiθ=cosθ+isinθ

Therefore,

ei712π=cos(712π)+isin(712π)

cos(712π)=cos(14π+13π)=cos(14π)cos(13π)sin(14π)sin(13π)

=(22).(12)(22)(32)

=264

sin(712π)=sin(14π+13π)=sin(14π)cos(13π)+cos(14π)sin(13π)

=(22).(12)+(22)(32)

=2+64

eiπ2=cos(π2)+isin(π2)=0+i.1=i

i2=1

Therefore,

ei712π.eiπ2=(26)+(2+6)i4(i)

=2+64+264i