Title

for example,  if you want

 13

-----  ,

 20

then you write

 

(13/20)  .

 

If you want

 x

---  ,

 y

then you write

 

(x/y)  .

 

If you want

     /     x*x + x      \

y* (      ----------    )     ,

     \      cos(z)     /

then you write y*((x*x+x)/(sin(z)))