1).(4x^3-6x^2)÷2x^2(2).(12m^2n+20mn)÷4mn(3).(9x^4-12x^3+54x^2)÷3x^2(4).(-14x^3y-21x^2y^2+63xy^3)÷(-7xy)谢谢了!

问题描述:

1).(4x^3-6x^2)÷2x^2(2).(12m^2n+20mn)÷4mn(3).(9x^4-12x^3+54x^2)÷3x^2(4).(-14x^3y-21x^2y^2+63xy^3)÷(-7xy)谢谢了!

1).(4x^3-6x^2)÷2x^2
=4x^3÷2x^2-6x^2 ÷2x^2
=2x-3
(2).(12m^2n+20mn)÷4mn
=12m^2n÷4mn+20mn÷4mn
=3m+5
(3).(9x^4-12x^3+54x^2)÷3x^2
=9x^4÷3x^2-12x^3÷3x^2+54x^2÷3x^2
=3x²-4x+18
(4).(-14x^3y-21x^2y^2+63xy^3) ÷(-7xy)
=-14x^3y ÷(-7xy)-21x^2y^2 ÷(-7xy)+63xy^3 ÷(-7xy)
=2x²+3xy-9y²