计算[5xy²(x²-3xy)-(-3x²y²）³]÷（-5xy）²
问题描述：
计算[5xy²(x²-3xy)-(-3x²y²）³]÷（-5xy）²
答
[5xy²(x²-3xy)-(-3x²y²）³]÷（-5xy）²
=（5x^3y²-15x²y^3+27x^6y^6）÷25x²y²
=0.2x-0.6y+1.08x^4y^4