化简：(1)-5(x^2-3)-2(3x^2+5) (2)2m-3n+[6m-(3m-n)]

化简：(1)-5(x^2-3)-2(3x^2+5) (2)2m-3n+[6m-(3m-n)]
化简：(1)-5(x^2-3)-2(3x^2+5) (2)2m-3n+[6m-(3m-n)]

化简：(1)-5(x^2-3)-2(3x^2+5) (2)2m-3n+[6m-(3m-n)]
(1)-5(x^2-3)-2(3x^2+5)
= -5x^2+ 15 -6x^2 -10
= -11 x^2 + 5
(2)2m-3n+[6m-(3m-n)]
= 2m -3n + 6m - 3m +n
= 5m -2n

(1)-5(x^2-3)-2(3x^2+5)
=-5x^2+15-6x^2-10
=-11x^2+5
(2)2m-3n+[6m-(3m-n)]
=2m-3n+6m-3m+n
=5m-2n
祝学习进步

解
-5(x²-3)-2(3x²+5)
=-5x²+15-6x²-10
=(-5x²-6x²)+(15-10)
=-11x²+5

2m-3n+[6m-(3m-n)]
=2m-3n+6m-3m+n
=(2m+6m-3m)+(n-3n)
=5m-2n

(1)原式=-5x^2+15-6x^2-10=-11x^2+5
(2)原式=2m-3n+6m-3m+n=5m-2n