计算3a^2bc乘（-2abc^2)-12a^5b^4c^7除以(-4a^2b^2c^4)
问题描述：
计算3a^2bc乘（-2abc^2)-12a^5b^4c^7除以(-4a^2b^2c^4)
答
3a^2bc乘（-2abc^2)-12a^5b^4c^7除以(-4a^2b^2c^4)
=-6a^3b^2c^3-3a^3b^2c^3
=-9a^3b^2c^3