Find-the-modulus-of-a-complex-number-Z-cos-40-i-sin-40-1-

Question Number 146782 by mathdanisur last updated on 15/Jul/21

F i n d t h e m o d u l u s o f a c o m p l e x

n u m b e r :

Z = c o s 40 + i s i n 40 + 1 = ?

Answered by Ar Brandon last updated on 15/Jul/21

z = e^{40 i} + 1 = e^{20 i} (e^{20 i} + e^{- 20 i})

= e^{20 i} (2 \cos 20) \Rightarrow∣ z ∣= 2 \cos (20)

Commented by mathdanisur last updated on 15/Jul/21

c o o l S e r t h a n k y o u

h o w d i d y o u c h a n g e i t a n d w r i t e i t

a s e e^{40 i} . ?

Commented by Ar Brandon last updated on 16/Jul/21

e^{i θ} = \cos θ + isin θ

Commented by mathdanisur last updated on 16/Jul/21

t h a n k s S e r