y=3x^5-5x^4-10x^3+30x^2-5x+1拐点 我知道是求二阶导数 我怎么就算出来个-1

用递归法求y=x-(x*x*x/3!)+(x*x*x*x*x/5!)-(x*x*x*x*x*x*x/7!)+. xy²/(x²y-y) × x²/(x²+x)=(x²-3x)/(x²-5x) × 2x-10/(x²-6x+9)=化简求植x²-1/(x²-x-2)除以x/2x-4,其中x=1/2[x-x/(x+1)]除以[x/(2x-4)] ,其中x=√2+1 （x+y-5)*（x+y-5)+（x-y+3)=0 x*x-y*y 已知:3x-5y=0,求x/y,x-y/y,x-y/x （5x+3y)(3y-5x)-(4x-y)(4y+x)= 5x^3y(x-y)^3-10x^4y^3(y-x)^2因式分解 5x^3y(x-y)^3-10x^4y^3(y-x)^2 5X^3Y(X-Y)-10X^4Y^3(Y-X)^2因式分解 (4x-2y-z)-{5x[8y-2y-(x+y)]-x+(3y-10z)]=? kuaihuajian 4(x-y)-3(x-y)=9 5(x-y)+2(x-y)=11 3(x+y)-4(x-y)=11,2(x-y)+5(x+y)=27 3(x+y)+2(x-y)=36 4(x+y)-5(x-y)=2 先化简再求值(x-y)(x-2y)+(x-2y)(x-3y)-2(x-3y)(x-4y) x=4 y=5 若2x-3y+4=0则x（x*x-1)+x(5-x*x)-6y+7 3(2X+Y)+(2(2x-Y)=6 (8X+4y)-(10X-5Y)=2 (4x-2y-z)-{5x-[8y-2z-(x-2y)]-x-(3y-10z)}=? 已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y) 3X=5Y （X+Y)*3X=(2Y+X)*4+2*2