You can put this solution on YOUR website! we know that every 2pi a full circle has been completed.
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In terms of pi/5 a full circle is 10pi/5
but we need 7pi/5 more. 5pi/5 = pi = 1/2 circle
so we need 2pi/5 more.
The terminal angle is 2pi/5.
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In terms of pi/2 a full circle is 4pi/2
16 circles = 64pi/2
so we need 3pi/2 more.
The terminal angle is -pi/2.
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In terms of pi/9 a full circle is 18pi/9
but this is 3pi/9 too much, so we come back 3pi/9 = pi/3
The terminal angle is pi/3.
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