Mathematics

Mathematics

Problem

Which function is continuous at x=0x=0 but NOT differentiable there? a) g(x)=1xg(x)=\dfrac{1}{x} b) h(x)=x2h(x)=x^{2} c) f(x)=∣x∣f(x)=|x| d) k(x)=∣x∣3k(x)=|x|^{3}
Intuitive explanation

The key is understanding that continuity and differentiability are different: a function can be unbroken at a point yet have a "sharp corner" or sudden change in slope there. Look for a function that passes through its point without jumping, but where the left and right derivatives don't match—or where the graph has a cusp or kink that prevents a single tangent line from existing.

Intuitive explanation

The key is understanding that continuity and differentiability are different: a function can be unbroken at a point yet have a "sharp corner" or sudden change in slope there. Look for a function that passes through its point without jumping, but where the left and right derivatives don't match—or where the graph has a cusp or kink that prevents a single tangent line from existing.

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