Discussion about math, puzzles, games and fun. Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫ • π ƒ ¹ ² ³ °
 

You are not logged in. #1 20130117 05:49:29
Little derivative problem (prove or give a counterexample)Hi guys, i'm trying to figure out if this is true or not, can you help me? 30+2=28 (Mom's identity) #2 20130117 06:22:12
Re: Little derivative problem (prove or give a counterexample)Not true. ƒ may only be piecewise differentiable, not wholly differentiable. where is chosen so that for continuity. Then if we make by piecing together the functions and their domains, this function satisfies all your given conditions but is not differentiable at any integer value of , where the gradient changes abruptly. Last edited by scientia (20130117 10:11:58) 