# How do you find the linear approximation L to f at the designated point P. compare the error in approximating f by L at the specified point Q with the distance between P and Q given #f(x,y) = 1/sqrt(x^2+y^2)#, P(4,3) and Q(3.92, 3.01)?

##### 1 Answer

May 31, 2016

#### Explanation:

The tangent plane

where

The normal vector to

Giving

At

so the tangent plane reads

Given a point

and a point

Their distance is