Find the equation of the tangent plane to the surface z=x2+3y2z = x^2 + 3y^2z=x2+3y2 at the point (1,2,13)(1, 2, 13)(1,2,13).
z−13=2(x−1)+6(y−2)z - 13 = 2(x - 1) + 6(y - 2)z−13=2(x−1)+6(y−2)
z−13=2(x−1)+12(y−2)z - 13 = 2(x - 1) + 12(y - 2)z−13=2(x−1)+12(y−2)
z=2x+12yz = 2x + 12yz=2x+12y
z−13=x−1+3(y−2)z - 13 = x - 1 + 3(y - 2)z−13=x−1+3(y−2)