How do you write the trigonometric form into a complex number in standard form 9(cos58+isin58)?

Sep 24, 2016

$9 \left(\cos 58 + i \sin 58\right) = 4.734 + i 7.632$

Explanation:

A complex number $r \left(\cos \theta + i \sin \theta\right)$ can be written into complex form as $a + i b$,

where $a = r \cos \theta$ and $b = r \sin \theta$

Hence $9 \left(\cos 58 + i \sin 58\right)$

= $9 \cos 58 + i 9 \sin 58$

= $9 \times 0.526 + i 9 \times 0.848$

= $4.734 + i 7.632$