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How do you determine the two coterminal angle (one positive one negative) for the angle #-420^circ#?

Answer 1

There are a countably infinite number of angles coterminal to #-420^circ;# we're free to add or subtract #360^circ# as many times as we like to come up with them. Adding once gives our negative answer, #-60^circ# and once more our positive answer, #300^circ.#

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Answer 2

Abigail Armstrong

To determine the two coterminal angles for the angle -420 degrees, you can add or subtract multiples of 360 degrees.

For the positive coterminal angle: -420 degrees + 360 degrees = -60 degrees

For the negative coterminal angle: -420 degrees - 360 degrees = -780 degrees

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.