Homework Statement
Suppose you need to know an equation of the tangent plane to a surface S at the point P(2,1,3). You don't know the equation for S but you know that the curves
r1(t)=<2+3t,1-t^2,3-4t+t^2>
r2(u)=<1+u^2,2u^3-1,2u+1>
both lie on S. Find an equation of the tangent plane at P...