What do the three mathematical symbols ∑, ∏ and τ mean? (They are not English letters)
They are all Greek letters, and the first symbol is pronounced Xigema, which means Jia Lian. For example: ∑x=6, (x= 1, 2,3) It is equivalent to 1+2+3=6. ∏ It says: Pie, yes; The meaning of multiplication, for example: ∏x=24, (x = 2,3,4), which is equivalent to 2*3*4=24. τ Pronunciation: Ti, a symbol of time, represents the amount of time.