- #1

PsychonautQQ

- 784

- 11

## Homework Statement

Find the equation of the normal line of function f(x,y) = x^2+y^2-1 through points (2,1,4)

## Homework Equations

(x-xo)/f_x = (y-yo)/f_y = (z-zo)/f_z

## The Attempt at a Solution

so...

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?