Answer:
The answer is "[tex]\bold{9.19- 9.19\ i}[/tex]"
Step-by-step explanation:
When the value of [tex]z_1[/tex] has the following properties:
[tex]\to |z_1| =13[/tex]
[tex]\theta = 315^{\circ} \\\\ = 1.75 \pi\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ _{where} \ \ (\pi = 180^{\circ})[/tex]
Calculating the value of [tex]z_1[/tex] :
[tex]= 13 \times [ \cos(1.75 \pi ) + i \sin(1.75 \pi) ] \\\\= 13 \times[\cos(1.75 \pi - 2\pi ) + \ i \sin(1.75 \pi - 2\pi )]\\ \\= 13 \times [\cos(-0.25 \pi ) +\ i \sin(-0.25 \pi) ]\\\\= 13 \times [0.707106781 - 0.707106781]\\\\ =9.19 - 9.19\ i \\\\[/tex]