Assuming K is a whole number, evaluate the following
\[\sin \frac{ \pi }{ 2 } + 2kpi\]
what is sin(pi/2) equal to
3pi/2
sin(pi/2) should equal to 1
because its on (0,1)?
sin ( pi/2 + 2*k * pi ) ?
ill re-type it hold on please
yes it equals to 1, since sin ( x + 2pi*k ) = sin x
\[\sin(\frac{ \pi }{ 2 } + 2kpi)\]
you can add a revolution of 2pi radians or multiples of a revolution to sin sin (Θ + 2pi * K ) = sin (Θ)
if you refresh your browser that will render properly
i dont understand
This is a trig identity: sin (theta + 2pi*k) = sin(theta) Hence: sin ( pi/2 + 2*k * pi ) = sin(pi/2)
HI!!
you got this or not?
no
ok lets go slow because it is really not hard at all
\[\sin(\frac{\pi}{2})=1\] a fact that you might should memorize, but you can see it from the unit circle
ok
the other thing you see from the unit circle is if you go around again, in other words if you add \(2\pi\) to any angle, you are right back where you started from
this is usually described by saying "sine is periodic with period \(2\pi\)" which just means if you add \(2\pi\) to any number the sine remains the same
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that means \[\sin(\frac{\pi}{2})=1=\sin(\frac{\pi}{2}+2\pi)=\sin(\frac{\pi}{2}+4\pi)=...\]
they are all one because they are all the same place on the unit circle this is more succinctly written as \(\frac{\pi}{2}+2k\pi\)
ok
all these angles : Pi/2, pi/2 + 2pi, pi/2 + 4pi , ... terminate at the same point on the unit circle
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