Precalculus
posted by Scarlet .
What is the answer and how did you do for this question? Please I really need help! :(
Express in rectangular form:
6(cos(4π)/(3)+i sin(4π)/(3)?

Precalculus 
Steve
just recall that x=rcosθ y=rsinθ
you have r=3, θ=4π/3
x = 6cos4π/3 = 6*(1/2) = 3
y = 6sin4π/3 = 6*(√3/2) = 3√3
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