Original
The critical points are the points where {{MATH_268}} or {{MATH_269}} does not exist. {{MATH_270}} is a
critical point, since we have already seen it is a point of
discontinuity for {{MATH_271}}, and thus {{MATH_272}} does not exist there. On the interval
{{MATH_273}}, {{MATH_274}} has a critical point at {{MATH_275}}.
On the interval {{MATH_276}}, {{MATH_277}} has a critical point at {{MATH_278}}. Mark the critical points {{MATH_279}}
and {{MATH_280}} on your plot. {{COMMENT_281}}