Question

Z = 6.8 e j 2.57 + 5.5 e j 2.64 put z in the form z = r ∠ θ , where r > 0 , θ is in degrees, and − 180 ∘ < θ ≤ 180 ∘ .

Answer 1

A suitable calculator* handles this easily. The one shown is a TI-83/84 work-alike. The first calculation is done in Radians mode. Since you want the answer in degrees, the second calculation is done in Degrees mode.

z = 12.29255119 ∠ 149.0434722°


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* You already need a calculator for the trig functions. You may as well use the other capabilities it offers.