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5. Let f : IR - R. Use the inequality -lal 3. 9. Show that the function below is continuous at 0. * sin(1) if # 0, if/as x = 0, 10. Prove that if the functions f and g are continuous at a and g(a) # 0, then the function & is continuous at a 11. Let J, g. h : R - R and a E R. Assume that f and g are continuous at a, f(a) = 9(a) and f(x) S h(x) 5 9(x) for all r E R. Prove that h is continuous at a