What is a Fulcrum?

The point where the lever acts as a support when fixed (except for the pulley). Extension refers to the key, center of things.

[zh din] Come on!

When leverage occurs

A fixed point at which a lever acts to support an object. Pivot point O: The fixed point around which the lever rotates.

Generally speaking, for a multi-valued function w = f (z), if the function value w is not restored around a point, and the value of each single-valued branch function at this point is the same, it is the fulcrum of the multi-valued function.

If z turns around the fulcrum n times and the function value w recovers, this point is called the n-1 order fulcrum of the multivalued function.

For example, the function w = sqrt (z). Obviously, the value of w is restored after two weeks around z = l along the fulcrum z = 0. Therefore, z = 0 is the first-order fulcrum of w = sqrt (z). In addition to z = 0, z = is also the first-order pivot of w = sqrt (z).