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(-1)的2011次方+(-2)+(-1/2)²-I-3I

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(-1)的2011次方+(-2)+(-1/2)²-I-3I
2×[3-(-2)²]+(-1/3-4/15﹚÷(-3/5)
先化简,再求值:1/2(-4x²+2x-1)-(x-1/2),其中x=1/2
(-1)的2011次方+(-2)+(-1/2)²-I-3I
(-1)的2011次方+(-2)+(-1/2)²-I-3I
=-1-2+1/4-3
=-6+1/4
=-23/4;
2×[3-(-2)²]+(-1/3-4/15﹚÷(-3/5)
=2×(3-4)+(-5/15-4/15)×(-5/3)
=-2+1
=-1;
先化简,再求值:1/2(-4x²+2x-1)-(x-1/2),其中x=1/2
1/2(-4x²+2x-1)-(x-1/2)
=-2x²+x-1/2-x+1/2
=-2x²
=-2×(1/4)
=-1/2;