(1)本题选D dy/dx =d[1+x-e^(-x)]/dx =0+1+e^x =1+e^x (2)本题选B ∫(2x-3x^2)dx(0→1) =(x^2-x^3)|(0→1) =1-1-(0-0) =0 (3)本题选A,第（1）步开始出错 令t=x^2 ∫xsin(x^2)dx(0→1) =(1/2)∫sin(x^2)d(x^2)(0→1) =(1/2)∫sintdt(0→1) =(1/2)(-cost)|(0→1) =(1/2)(1-cos1)
答：1)因为Z=2×x的立方+3x×cosy+3×y 所以 Dx=6*x的平方+3×cosy Dy=3x×siny+3 再将x=1,y=0代入的: Dx=6+3=9...详情>>
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