2(x^3)^2乘x^3-(2x^3)^3+(-5x)^2乘x^7
问题描述：
2(x^3)^2乘x^3-(2x^3)^3+(-5x)^2乘x^7
答
2(x³)²*x³-(2x³)³+(-5x)²*x^7
=2x^6*x³-8x^9+25x²*x^7
=2x^9-8x^9+25x^9
=19x^9