Question

What is 56(cos(33) + i sin(33)) = 7(cos(11°) + i sin(11°))?

O 8(cos(30) + i sin(3))
49(cos(30) + i sin(30))
8(cos(22) + i sin(22°))
O 49(cos(22) + i sin(22'))

Answer 1

Explanation:

56(cos(33) + i sin(33)) = 7(cos(11°) + i sin(11°))

Divide both sides by 7 to get;

8(cos(33) + i sin(33)) = (cos(11°) + i sin(11°))

Expanding and Rearranging gives;

8cos(33) + 8i sin(33)) - cos(11) - isin(11)

This gives ;

8Cos(22) + 8i sin(22) = 8(Cos(22) + I sin(22)