(-3x^4y^2)^2÷(-2/3x^ny^2)=-mx^8y^29x^8y^4÷(-2/3x^ny^2)=-mx^8y^29÷(-2/3)*x^(8-n)y^(4-2)=-mx^8y^29*(-3/2)*x^(8-n)y^(4-2)=-mx^8y^2-27/2*x^(8-n)y^2=-mx^8y^2m=-27/28-n=8n=0所以m=-27/2,n=0
