How do you express the complex number in rectangular form: z=5(cos 120degrees + i sin 120 degrees)z=5(cos120degrees+isin120degrees)?
1 Answer
Feb 18, 2016
(-5/2 , 5/2sqrt3 )(−52,52√3)
Explanation:
using the formulae that links Polar to Rectangular coordinates.
• x = rcostheta ∙x=rcosθ
• y = rsintheta ∙y=rsinθ here r = 5 and
theta = 120^@ θ=120∘ hence :
x = 5cos120^@ = 5 xx -1/2 = -5/2 x=5cos120∘=5×−12=−52 and
y = 5sin120^@ = 5 xxsqrt3/2 = 5/2 sqrt3 y=5sin120∘=5×√32=52√3