First, let's imagine the point 3 + 4j as a point on an Argand diagram, with coordinates 3,4. The polar form of an imaginary number is in the form re^(jθ), where r is the modulus of the number (the distance between the point on the graph and the origin), and θ is the argument (the angle the point makes with the horizontal). In order to find r, we can simply use Pythagoras' Theorem, giving us the answer r = 5. To find θ, we must use trigonometry, identifying the angle θ as the inverse tangent of (4/3), which is equal to 0.927. Therefore the angle θ is 0.927. This means the polar form of 3 + 4j is 5e^0.927jθ
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