Trigonometry Lecture Notes, Section 6.1

The domain of y = cos-1x is [-1, 1] and the range is . It helps to think of the range of y = cos-1x as being along the top half of the unit circle, which is traced out as angles range from 0 to . If you restrict the domain of y = tan x to the interval as shown below, the restricted function is one-to-one. The . inverse tangent function ................
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