Original
A function on a {{CMD_1}}closed{{CMD_2}} interval must have a local extremum.
{{CMD_3}}
Think of {{MATH_4}}, on {{MATH_5}}. The function has no critical points, therefore, no local extrema.
{{CMD_6}}
{{CMD_7}}
{{CMD_8}}True{{CMD_9}}
{{CMD_10}}False{{CMD_11}}
{{CMD_12}}