# List of functions used for tangent/normal 2D.
# An item in this list will be picked randomly at each exercise.
# Structure of item: multi-line.
# line 1 is function description.
# line 2 is derivative.
# line 3 is proportionality
# The rest is values for parameters c1, c2, etc.

:c1*cos(c2*t),c3*sin(c4*t)
 -c1*c2*sin(c2*t),c3*c4*cos(c4*t)
 1
 1.2,1.3,1.4,1.5,1.6,1.7,1.8,2,2.2,2.5,2.7,3
 2,4,8
 1.2,1.3,1.4,1.5,1.6,1.7,1.8,2,2.2,2.5,2.7,3
 3,5,7,9
:c1*cos(c5*t)+c2*t,c3*sin(c5*t)+c4*t
 -c5*(c1)*sin(c5*t)+c2,c5*c3*cos(c5*t)+c4
 1.5
 1.1,1.2,1.3,1.4,1.5,1.6,1.7,1.8,1.9,2
 -2,-1.8,-1.5,-1.1,-0.7,-0.5,-0.3,-0.2,-0.1,0.1,0.2,0.3,0.5,0.7,1.1,1.5,1.8,2
 1.1,1.2,1.3,1.4,1.5,1.6,1.7,1.8,1.9,2
 -2,-1.8,-1.5,-1.1,-0.7,-0.5,-0.3,-0.2,-0.1,0.1,0.2,0.3,0.5,0.7,1.1,1.5,1.8,2
 2,3,4

