z=−3−8iFind the angle θ (in degrees) that z makes in the complex plane.Round your answer, if necessary, to the nearest tenth. Express θ between −180∘ and 180∘.θ=□∘
Q. z=−3−8iFind the angle θ (in degrees) that z makes in the complex plane.Round your answer, if necessary, to the nearest tenth. Express θ between −180∘ and 180∘.θ=□∘
Identify real and imaginary parts: Identify the real and imaginary parts of the complex number z.z=−3−8i, where the real part is −3 and the imaginary part is −8.
Calculate the argument of z: Calculate the argument of z, which is the angle θ in the complex plane.The argument of z is given by θ=arctan(real partimaginary part)=arctan(−3−8).
Use calculator to find theta in radians: Use a calculator to find the value of θ in radians.θ=arctan(−8/−3)=arctan(8/3).Since we need the angle in degrees, we will convert it after calculation.
Convert radians to degrees: Convert the angle from radians to degrees. θ in degrees = arctan(38)×(π180).
Calculate theta in degrees: Calculate the angle θ in degrees using a calculator.θ in degrees ≈arctan(38)×(π180)≈69.4∘. However, since both the real and imaginary parts of z are negative, z lies in the third quadrant, and the angle should be adjusted to be between −180∘ and 180∘.
Adjust angle for correct quadrant: Adjust the angle for the correct quadrant.In the third quadrant, the angle θ should be negative and we add 180° to the calculated angle to get the angle in the correct range.θ=69.4°−180°=−110.6°.
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