MathematicsEasy179×since 2002Q4188Let K be the set of all real values of x where the function f(x) = sin |x| – |x| + 2(x – π\piπ) cos |x| is not differentiable. Then the set K is equal to :A{0, π\piπ}Bϕ\phiϕ (an empty set)C{ r }D{0}Check answerSkip