(x+y-z)+(x-y+z)-(x-y-z)和a-2(2a+b)+3(a-b)
提公因式法(急!(x+y+z)(x-y+z)+(y-x+z)(y-x-z)和a(a-b-c)+b(c-a+b)+c(b-
(1) (a+2b/a-b)+(b/b-a)-(2a/a-b); (2) (y/x-y+z)+(2x+z/y-x-z)-
(a+2b-1)²与(2x+y+z)(2x-y-z)这两题请详解,
(-2a-b)②-(-2a+b)(-b-2a) (x-y+z)(-x+y+z)+(x-y)②其中z=-1
(a-b+c)(-a+b+c)(3a+b-2)(3a-b+2)(x+2y-3z)(x-2y+3z)
、 #define M(x,y,z) x*y+z main() { int a=1,b=2,c=3; printf("%
计算:1:(2a-3b-c)^2 2:(3y-y-1)(y-3x-1) 3:(2x+y-z)(z-2x+y)
解方程组:X+Y-3Z=2A X-3Y+Z=2B _3X+Y+Z=2C
已知方程组{x+y+z=2,2x-y+z=-1,x+3y+4z=3的解是{x=2-a,y=-2b,z=2-3c,那么a,
已知X+Y+Z=a,XY+YZ+XZ=b,求X*X+Y*Y+Z*Z的值
∮τ (y-z)dx+(z-x)dy+(x-y)dz,τ为椭圆x^2+y^2=a^2,x/a+y/b=1
已知x,y,z是三个非负数,并且满足3x+2y+z=5,2x+y-3z=1.设k=3x+y-7z,记a为k的最大值,b为