Rational number I believe so
Exercise 1:
The easiest way to compute powers of complex numbers is to write them in the form

In this form, you have

The magnitude of the number is given by

So, we have

As for the angle, we have

So, we have

Finally,

Exercise 2:
You simply have to compute the trigonometric function:

So, we have

Answer:
$8.
Step-by-step explanation:
See attached picture.
Answer:
Add the two angles: 43° + 47° = 90°.
Step-by-step explanation:
A right triangle has an angle that equals 90°. Complementary angles equal 90°. Therefore, if you add these two angles, you will know whether or not △ABC is a right triangle. Triangle △ABC is broken up into two angles, m∠ABD and m∠DBC. When the measures m∠ABD and m∠DBC are added together, they equal 90°, and thus, form a complementary angle.
Hope this helps,
♥<em>A.W.E.</em><u><em>S.W.A.N.</em></u>♥