x^4y-7x^2y^2+6-3xy^3-4x^3按字母x的降幂排列和按y的升幂排列,
问题描述:
x^4y-7x^2y^2+6-3xy^3-4x^3按字母x的降幂排列和按y的升幂排列,
答
x^4y-7x^2y^2+6-3xy^3-4x^3
=x^4y-4x^3-7x^2y^2-3xy^3+6...按x降幂
=-4x^3+x^4y-7x^2y^2-3xy^3+6...按y升幂