## anonymous 5 years ago Hi I have a Calc 2 question... Assume that the continuously differentiable vector-based function r(t) = (x(t),y(t)), a < t < b and models a level curve of the real valued function f(x,y) = y^2 + x^2y-2x^4+3 also assume that r(1) = (1,1) Find a vector model for the tangent line to r(t) at r(1). I just have no idea where to start with this any help is appreciated thanks.

You should get the concepts clear at first. Level curve means there is a constant c so that $\forall t \in (a,b): f(x(t), y(t)) = c$ So by inserting the given starting point you can calculate the constant c.