A student was asked to find the equation of the tangent plane to the surface z=x^3-y^2 at the point (x,y)=(2,3). The student’s answer was z= 3x^2(x-2)-2y(y-3)-1.
a)At a glance, how do you know this is wrong?
b)What mistake did the student make?
c)Answer the question correctly.