解(-3x²y)(-4x²y²-5y³-6x+1)=(-3x²y)(-4x²y²)+(-3x²y)(-5y³)+(-3x²y)(-6x)-3x²y=12x^4y³+15x²y^4+18x³y-3x²y3x²y(-4x²y+2xy...3a的平方（a的立方b的平方-2a）-4a(-a的平方b)的平方解3a²(a³b²-2a)-4a(-a²b)²=3a^5b²-6a³-4a(a^4b²)=3a^5b²-6a³-4a^5b²=-6a³-a^5b²