约分3a^3b^4-4a^4b^3/3a^4b^3-4a^3b^4/代表分式的符号上边是分母下边是分子请帮忙解答,

约分3a^3b^4-4a^4b^3/3a^4b^3-4a^3b^4
/代表分式的符号上边是分母下边是分子请帮忙解答,

a^3b^3(3b-4a)/((3a-4b)a^3b^3)=(3b-4a)/(3a-4b)