91Ó°ÊÓ

In Exercises 1-12, write each expression as a complex number in standard form. If an expression simplifies to either a real number or a pure imaginary number, leave in that form. $$ \sqrt{-20} $$

In Exercises 1-20, graph the curve defined by the following sets of parametric equations. Be sure to indicate the direction of movement along the curve. $$ x=-3 t, y=t^{2}+1, t \text { in }[0,4] $$

In Exercises 1-12, graph each complex number in the complex plane. $$ -2-4 i $$

In Exercises 1-20, find the product \(z_{1} z_{2}\) and express it in rectangular form. $$ z_{1}=4\left(\cos 80^{\circ}+i \sin 80^{\circ}\right) \text { and } z_{2}=2\left(\cos 145^{\circ}+i \sin 145^{\circ}\right) $$

In Exercises 1-10, plot each indicated polar point in a polar coordinate system. $$ \left(4, \frac{11 \pi}{6}\right) $$

In Exercises 1-12, graph each complex number in the complex plane. $$ -3-2 i $$

In Exercises 1-10, plot each indicated polar point in a polar coordinate system. $$ \left(1, \frac{2 \pi}{3}\right) $$

In Exercises 1-12, write each expression as a complex number in standard form. If an expression simplifies to either a real number or a pure imaginary number, leave in that form. $$ \sqrt{-24} $$

In Exercises 1-20, find the product \(z_{1} z_{2}\) and express it in rectangular form. $$ z_{1}=3\left(\cos 130^{\circ}+i \sin 130^{\circ}\right) \text { and } z_{2}=4\left(\cos 170^{\circ}+i \sin 170^{\circ}\right) $$

In Exercises 1-20, graph the curve defined by the following sets of parametric equations. Be sure to indicate the direction of movement along the curve. $$ x=t^{2}-1, y=t^{2}+1, t \text { in }[-3,3] $$