Gradient field of a Function for 2 Variables

[b]Task[/b][br]Change the parameters a, b, step and length by using the sliders.[br]Why does the gradient field not change when b is changed? [br][br]Explore the gradient field of other function, e. g. for [br]f(x,y) = x*y , f(x,y) = sin(x) cos(y) , f(x,y) = 0.5*exp(x)*y etc.

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