Yes There is no imaginary number before the new curriculum reform. 1998 people's education edition, mathematics in senior two is compulsory, and now the new senior high school entrance examination has been implemented. This imaginary number is placed in Chapter 7 of Compulsory 2. Imaginary number is the product of imaginary number, real number and imaginary unit, that is, a complex number with zero real part (such as 3i).