2x^2-{-3x+5+[4x^2-(-3x^2-x-1)]}-3,其中x=-3_数学解答

2x^2-{-3x+5+[4x^2-(-3x^2-x-1)]}-3,其中x=-3

人气：456 ℃　时间：2020-01-25 05:43:30

解答

2x^2-{-3x+5+[4x^2-(-3x^2-x-1)]}-3
=2x^2+3x-5-[4x^2-(-3x^2-x-1)]-3
=2x^2+3x-8-[4x^2-(-3x^2-x-1)]
=2x^2+3x-8-4x^2+(-3x^2-x-1)
=-2x^2+3x-8+(-3x^2-x-1)
=-2x^2+3x-8-3x^2-x-1
=-5x^2+2x-9
=-5*(-3)^2+2*(-3)-9
=-45-6-9
=-60