先化简再求值:3a^2b-[2a^2b-(2abc-a^2b)-4a^2c]-abc,其中a=-2,b=-3,c=1

先化简再求值:3a^2b-[2a^2b-(2abc-a^2b)-4a^2c]-abc,其中a=-2,b=-3,c=1
先化简再求值:3a^2b-[2a^2b-(2abc-a^2b)-4a^2c]-abc,其中a=-2,b=-3,c=1

先化简再求值:3a^2b-[2a^2b-(2abc-a^2b)-4a^2c]-abc,其中a=-2,b=-3,c=1
3a²b-[2a²b-(2abc-a²b)-4a²c]-abc
=3a²b-[2a²b-2abc+a²b-4a²c]-abc
=3a²b-2a²b+2abc-a²b+4a²c-abc
=abc+4a²c
=ac(b+4a)
当a=-2 ,b =-3 ,c =1时,
原式=-2×(-3-8)
=22

3a^2b-[2a^2b-(2abc-a^2b)-4a^2c]-abc
= 3 a ^ 2 b - 【2 a^ 2b - 2abc + a^ 2b - 4 a ^ 2 c】-abc
= 3 a^2b - 2 a^2b + 2abc - a^2b + 4a^2c - abc
= 4 a^2c + abc
当 a = - 2 ，b = - 3 ，c = 1 时，原...

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3a^2b-[2a^2b-(2abc-a^2b)-4a^2c]-abc
= 3 a ^ 2 b - 【2 a^ 2b - 2abc + a^ 2b - 4 a ^ 2 c】-abc
= 3 a^2b - 2 a^2b + 2abc - a^2b + 4a^2c - abc
= 4 a^2c + abc
当 a = - 2 ，b = - 3 ，c = 1 时，原式 = 4 × （- 2）^（2 × 1）+ （- 2）（- 3）× 1
= 4 × 4 + 6
= 22

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