化简3(a²-ab+2b²)-2(a²+2ab-3b²)先化简,再求值:2(x²-2x-1)-3(3x-2)+5(x-1),其中x=﹣2

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化简3(a²-ab+2b²)-2(a²+2ab-3b²)先化简,再求值:2(x²-2x-1)-3(3x-2)+5(x-1),其中x=﹣2
化简3(a²-ab+2b²)-2(a²+2ab-3b²)
先化简,再求值:2(x²-2x-1)-3(3x-2)+5(x-1),其中x=﹣2

化简3(a²-ab+2b²)-2(a²+2ab-3b²)先化简,再求值:2(x²-2x-1)-3(3x-2)+5(x-1),其中x=﹣2
3(a²-ab+2b²)-2(a²+2ab-3b²)
=3a²-3ab+6b²-2a²-4ab+6b²
=a²-7ab+12b²
2(x²-2x-1)-3(3x-2)+5(x-1)
=2x²-4x-2-9x+6+5x-5
=2x²-8x-1
=8+16-1
=23