Pronunciation: fai
F is a vector function L, and its integral path (which is a closed curve) ds represents the differential of its integral path, and it is also a product of vector f ds =fx*dx+fy*dy f=fxi+fyj(i j is the unit vector on the x y axis.
Available range
This symbol is often used to mean "feather" and "title" on the Internet. Also used for Ampere Loop Law:
When used as a feather, it is used with "".
Sogou typing, QQ typing and intelligent ABC can all be used to type this symbol. In the item of "Mathematical Symbol", you can enter it with the keypad.