Answer
$||P||=max$ {$x_1-x_0, x_2-x_1, ....,x_n-x_{n-1} $}
Work Step by Step
The mesh or norm of a partition of a closed interval $[a,b]$ is denoted as $||P||$ and can be defined as
$||P||=max$ {$x_1-x_0, x_2-x_1, ....,x_n-x_{n-1} $}
where, $a=x_0 \lt x_1 \lt x_2 \lt ....\lt x_{i-1} \lt x_i \lt ....\lt x_{n-1} \lt x_n=b$
