计算：(-3x³）²乘x³+（-x²）乘x七次方-（5x³）³
问题描述：
计算：(-3x³）²乘x³+（-x²）乘x七次方-（5x³）³
答
(-3x³）²*x³+（-x²）*x^7-（5x³）³
=9x^6*x^3-x^9-125x^9
=9x^9-x^9-125x^9
=(9-1-125)x^9
=-117x^9