f(x) = (x * sin(x))
A = Point(xAxis)
A': (x(A), f(x(A)))
A'': (0, y(A'))
u = Vector(A', A'')
piirto1: PolyLine[(1.6434E0,5.0583E-2), (1.5993E0,1.6526E-1), (1.5552E0,2.4465E-1), (1.4406E0,3.0640E-1), (1.3259E0,3.5050E-1), (1.2288E0,3.9461E-1), (1.1142E0,4.0343E-1), (1.0260E0,4.2107E-1), (9.3775E-1,4.3872E-1), (7.4368E-1,4.3872E-1), (5.5843E-1,4.2990E-1), (4.6140E-1,4.0343E-1), (3.6437E-1,3.4168E-1), (2.2323E-1,2.2701E-1), (1.6148E-1,1.3880E-1), (1.2619E-1,6.8226E-2), (1.2619E-1,-7.2914E-2), (1.2619E-1,-1.9641E-1), (1.4384E-1,-2.8462E-1), (1.7912E-1,-4.0812E-1), (2.1441E-1,-4.9633E-1), (3.0262E-1,-6.0219E-1), (3.8201E-1,-6.9922E-1), (4.7904E-1,-7.7861E-1), (5.6726E-1,-8.3154E-1), (6.8193E-1,-8.7564E-1), (9.5539E-1,-8.8447E-1), (1.1583E0,-8.7564E-1), (1.2730E0,-8.4918E-1), (1.3788E0,-7.7861E-1), (1.4935E0,-6.4629E-1), (1.5552E0,-5.6690E-1), (1.5905E0,-4.6105E-1), (1.6258E0,-3.1991E-1), (1.6434E0,-2.1405E-1), (1.6434E0,-7.2914E-2), (1.6434E0,5.0583E-2), (1.5993E0,1.6526E-1), (1.5376E0,2.8876E-1), (1.4670E0,3.5050E-1), (1.3965E0,3.5050E-1), (1.3082E0,3.5050E-1), (NaN,NaN), true]