Euler Spiral

var('t') a=1 b=0 pts = [ (numerical_integral(cos(a*x^2 + b*x), 0, t, max_points=100)[0], numerical_integral(a*sin(x^2)+b*x, 0, t, max_points=100)[0])for t in [0.1..2*pi,step=0.01]] list_plot(pts,aspect_ratio=1)