Homework Sourse35 Explain why the function fxy arctanx2 y2 1 is different
3.5) Explain why the function f(x,y) = arctan(x^2 + y^2 +1) is differentiable at the point
(x,y) = (1,0). In your explanation you must quote appropriate results from class and the
textbook. [Note: d(arctan(x)) / dx = 1 / 1+x^2 .]
Solution
limit(dejta x->0) arctan( (delta x +1 )^2 + 0^2 +1 ) - arctan(1^2 + 0^2 +1) / delta x exist limit (dejta x->0) arctan( (delta y +0 )^2 + 1^2 +1 ) - arctan(0^2 +1^2 +1) / delta y exist
