Limits Continuity and Differentiability

Appeared 179 times across 23 years of JEE Main papers — about 7.8 questions a year. Every one of them is below, with a full worked solution.

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01Easy179×since 2002Q4188

Let K be the set of all real values of x where the function f(x) = sin |x| – |x| + 2(x –

\pi

) cos |x| is not differentiable. Then the set K is equal to :