Please show the entire question. What are you trying to do with these problems?
Answer:
C. 47°
Step-by-step explanation:
The angle between the terminal ray of 227° and the nearest x-axis (the negative x-axis) is ...
227° -180° = 47°
The reference angle is 47°.
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In mathematical terms the reference angle is the minimum of the angle modulo 180° and the supplement of that angle.
227° modulo 180° = 47°
180° -47° = 133° . . . . supplement of 47°
min(47°, 133°) = 47° . . . the reference angle
Answer:
±90
Step-by-step explanation:
√(-225) · √(-36) = (15i)·(6i) = 90i² = 90·(-1) = -90
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On the other hand, ...
... √(-225) · √(-36) = √((-225)·(-36)) = √8100 = 90
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If you consider all the roots at each stage, the result is ±90. Since you're working with complex numbers here, it is reasonable to recognize every number has two square roots.
... √(-225) = ±15i
... √(-36) = ±6i
... √(-225) · √(-36) = (±15i)·(±6i) = ±90i² = ±90
Answer: -18, -15, -5, 0, 9, 18
