Precalculus

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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 -

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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