Express the complex number in trigonometric form.
1 answer:
-5i can be written as 0 + (-5)i
It is in the form a+bi where a = 0 and b =-5
So the point (a,b) is (0,-5)
The distance from the origin to this point is 5 units, therefore r = 5. This is the magnitude.
The angle is 270 degrees as shown in the attached image. You start on the positive x axis and rotate until you reach the point (0,-5)
This is why the answer is choice A) 5(cos(270) + i*sin(270))
It is in the form a+bi where a = 0 and b =-5
So the point (a,b) is (0,-5)
The distance from the origin to this point is 5 units, therefore r = 5. This is the magnitude.
The angle is 270 degrees as shown in the attached image. You start on the positive x axis and rotate until you reach the point (0,-5)
This is why the answer is choice A) 5(cos(270) + i*sin(270))
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Answer:
18.326 inches
Step-by-step explanation:
The question is basically asking us to find the arc length that the tip of the minute hand travels. The formula for an arc length is S=θr. So we need th find the angle that the minute hand passes through. We know that there is 360 degrees in a cicle and there is 12 stops around a clock, so divide 360 by 12 to find the degrees the minute hand travels every 5 minutes. We ge that every 5 minutes the hand travels 30 degrees, and 35 minutes is 7*5 so we multiple 30*7 to find the angular displacement, and we get 210 degrees. This equation uses radians though so we have to convert, which can be done doing , and we ge that θ is
so (
)(5)= 18.326 inches