sine graph

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1

<p>Is sin 2(x+pi) = sin 2x?</p>

<p>The answer is yes, but why? I can't seem to figure out the logic, because when I look at the equation, it obviously looks like the left hand side equation has been shifted horizontally. Can someone please explain? (Don't tell me to graph it on my calculator)</p>

2

<p>sin 2(x+pi) is the same as sin (2x+2pi). Since 2pi is one full rotation around the unit circle, the 2 equations are the same thing.</p>

3

<p>Sine has a period of 2kPi</p>

<p>It is 2pi (distribute), so k=1 which is in zeta</p>

<p>Thus they are same thing.</p>