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// View Axes should be turned on in view menu O=(0,0) // Hide point u=Circle[O,1] P=Point[u] // move P away from x-axis A=(1,0) // hide A t=angle[A,O,P] // turn off the label t'=arc[u,O,P] // color arc red and use style to make the arc thickness 5 // graph the length of arc AP on the x-axis X=(t,0) // turn off label tseg=Segment[O,X] // color segment red and use style to make the thickness 5 // play with moving P //make right triangle OPB B=(x(P),0) tri=polygon[O,P,B] // color segment PB green // make show hide button for tri S=(t,y(P)) sin=locus[S,P]