In this lesson, the teacher reviews how to graph the tangent function and then applies that knowledge to graph y equals the tangent of x over 3. The key takeaway is that the period of the tangent function is pi, but when the function is multiplied by a constant (in this case, 1/3), the period is stretched or compressed accordingly. As a result, the period of y equals tangent x over 3 is 3 pi.
Graphing y = tan(x/3)) and stating period. Solutions to a Review for a Trigonometry Test for a class. . See pdf on that site under Trig, special videos.
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