计算：(6x^4y-10x^3Y^2+14x^2y^5)/(-2x^2y)(6x^4y-10x^3Y^2+14x^2y^5)/(-2x^2y)（2/3a^4b^4-1/9a^2b^3）/(-1/3ab)^2[3a(2a)^2-(4a)^2+8a^2/(-2a)]/(4a)(21x^5y^3-6x^4y^3z+3x^3y^4)/(-1/3x^3y^3)

计算：（3x-4y）-[-（2y+x）+（x-3y）]-6x 计算:1/(x-y)-1/(x+y)-2y/(x^2+y^2)-4y^3/(x^4+y^4)-8x^7/(x^8+y^8) 1.计算(a^2+a+1)(a^2-a+1) 2.计算(x-y)(x+y)+(3x-2y)(2x+y)-x(6x-y) 计算（2x-3y)(x+4y)-(3x+y)(x-2y)（2x-3y)(x+4y)-(3x+y)(x-2y) 计算.2x÷x/5x+3y^2-4y+4/2y-6·1/y+3÷12-6y/9-y^2 (x-3y)(y+2x)-(4y-3x)(3x+4y)计算 计算:(x-y)^2*(x+y)^3*(-x-y)^3*(y-x)^4 计算：(x-y)^7÷(y-x)^6+(-x-y)^3÷(x+y)^2 计算(x-y)^7÷(y-x)^6+9-x-y)^3÷(x+y)^2 计算:(x+3y)(2x-y) 计算:(2x-3y)(x+y) 计算:(-x-2y) * (3x-y) 计算：(x+y)-3(x-2y). 计算(36x ^4y^3-24x^3y^2+3x^2y^2)/(-6x^2y) 计算:(x+y)^2×(-x-y)^3×[-3/4(x-y)^3]×5/6(y-x)^2 计算:(x+y)^2×(-x-y)^3×[-3/4(x-y)^3]×5/6(y-x)^2 导数的计算练习题导数的计算（1）y=x^5 （2)y=sinx(3)y=1/x^3(4)y=5^√x(5)y=cosx(6)y=5^x(7)y=log3^x(8)y=lnx(9)f(x)=x^3-x^2-x+1(10)y=2x^3-3x^2+4x-1(11)y=x inx（12）y=xsinx-cosx(13)y=cosx/x(14)y=3x(x^2+2)(15)f(x)=(x-1)^2+3(x-1)(16)f(x)=1 [(x+2y)(x-2y)+4(x-y)^2-6x]/(6x)计算