Find an equation of the tangent plane to the given surface at the specified point. z = 3(x − 1)2 + 2(y + 3)2 + 7, (5, 1, 87)

Respuesta :

Answer:

So for the point (5, 1, 87) the normal vector to surface is given by:

 fx(5,1) = [6(5) – 6] ,             fy(5,1)= [4(1) +12]

 fx(5,1) =(30 – 6)                     fy (5,1) = 16

 fx(5,1) = 24

Step-by-step explanation:

Equation is z = 3(x -1)2 + 2(y +3)2 + 7

Z= 3(x2+1-2x) +2(y2+6y+9)+7

 = 3x2- 6x + 2y2 + 12y + 28

Rearrange the equation of the surface into form f(x, y, z) = 0

f(x, y, z) = 3x2- 6x + 2y2 + 12y + 28 - z

∆f(x,y,z) = ∂f/∂x i + ∂f/∂y j+ ∂f/∂z k

Partially differentiate with respect to variable:

              = ∂/∂x (3x2- 6x + 2y2 + 12y + 28 - z) i + ∂/∂y (3x2- 6x + 2y2 + 12y + 28 - z) j +∂/∂z (3x2- 6x + 2y2 + 12y + 28 – z) k

             =(6x-6)i + (4y + 12 )j +(-1)k

So for the point (5, 1, 87) the normal vector to surface is given by:

 fx(5,1) = [6(5) – 6] ,             fy(5,1)= [4(1) +12]

 fx(5,1) =(30 – 6)                     fy (5,1) = 16

 fx(5,1) = 24