Find the equation of the normal line of function f(x,y) = x^2+y^2-1 through points (2,1,4)
(x-xo)/f_x = (y-yo)/f_y = (z-zo)/f_z
The Attempt at a Solution
f_x = 2x = 4
f_y = 2y = 2
f_z = ???
I don't know how to solve for f_z....
here is random stuff I was doing that *might* be related?
f(x,y) - z = 0
f(x,y) = z = 4
yeah.. any math guru wanna show this grasshopper the way?