Question Detail

MTH 101 MTH 101 Past Questions Objective Question

Question

Polar form of \(z = 4 + 4\sqrt{3}i\) is
Options
A \(8(\cos\frac{\pi}{3} + i\sin\frac{\pi}{3})\)
Correct Answer
B \(4(\cos\frac{2\pi}{3} + i\sin\frac{2\pi}{3})\)
C \(8(\cos\frac{2\pi}{3} + i\sin\frac{2\pi}{3})\)
D \(4(\cos\frac{\pi}{3} + i\sin\frac{\pi}{3})\)
Correct Answer

Option A is the correct answer.

Detailed Explanation

Modulus = √(4² + (4√3)²) = √(16+48)=√64=8. Argument = tan⁻¹(4√3/4)=tan⁻¹(√3)=π/3. So polar form is 8(cos π/3 + i sin π/3).

Hint

Find r = √(a²+b²) and θ = tan⁻¹(b/a).

Question Info