AP DSC School Assistant Math Model Test 1

Concept:The modulus of a complex number measures its magnitude, which is the distance from the origin in the complex plane.Explanation:Consider the complex number $z = a + ib$, where $a$ is the real part and $b$ is the imaginary part.The modulus is defined as $|z| = \sqrt{a^2 + b^2}$.This formula comes from the Pythagorean theorem, treating $(a, b)$ as coordinates.Thus, for $a + ib$, the modulus is $\sqrt{a^2 + b^2}$.Answer:Option A: $\sqrt{a^2 + b^2}$