(a^12)^3*a^7/(a^3)^7=a^36*a^7/(a^3)^7=a^43/(a^3)^7=a^43/a^21=a^22
(а^12)^3 *а^7/(а^3)^7=a^36*a^7/a^21=a^43/a^21=a^22
