Find the fourth roots of 81(cos 320° + i sin 320° ). write the answer in trigonometric form.

Using the De Moivre's Theorem, let us work out for the fourth roots of 81(cos 320° + i sin 320° ).

zⁿ = rⁿ (cos nθ + i sin nθ) 
z⁴ = 81(cos 320° + i sin 320° ) 
z = ∜[81(cos 320° + i sin 320° )] 
= ∜[3^4 (cos 4*80° + i sin 4*80°)] 
= 3(cos 80° + i sin 80°) 

idc

step-by-step explanation:

idk

if you are looking for the unit rate then the answer would be 9 because unit rate is distance divided by time.

step-by-step explanation: