规定2!=2x1

对于实数x1,x2规定min{x1,x1}为x1,x2中较小的数,若函数y=2-(x的平方)函数z=x,则min{y,z}的最大值为对于实数x1,x2规定min{x1,x1}为x1,x2中较小的数,若

F(x)=x²+4X+3在(负无穷大,-2)求减函数老师规定要设X1F(x)=x²+4X+3在(负无穷大,-2)求减函数老师规定要设X1F(x)=x²+4X+3在(负无穷

min=2*x1+3*x2;x1+x2>=350;x1>=100;2*x1+x2min=2*x1+3*x2;x1+x2>=350;x1>=100;2*x1+x2min=2*x1+3*x2;x1+x2>

疑难数学问题火急求助x1^3-3x1^2+2x1+x2→x1（x1^2-2x1+2-x1）+x2→x1（3-x1）+x2(怎么算出3-X1的)→3x1-x1^2+x2=2x1-x^2+x1+x2=-(

1x1/2+1/2x1/3+1/3x1/4+.+1/19x1/20=?1x1/2+1/2x1/3+1/3x1/4+.+1/19x1/20=?1x1/2+1/2x1/3+1/3x1/4+.+1/19x1

(-1x1/2)+(-1/2x1/3)+(-1/3x1/4)+...+(-1/2004x1/2005)=?(-1x1/2)+(-1/2x1/3)+(-1/3x1/4)+...+(-1/2004x1/2

若A1={1,2,3}A2={1,2},规定一个新定义A1+A2=｛X|X1+X2,且X1∈A1,X2∈A2｝求这个集合所有子集个数若A1={1,2,3}A2={1,2},规定一个新定义A1+A2=｛

有一数列：x1,x2,x3,.,x（n-1）,xn,规定x1=2,x2-x1=4,x3-x2=4,.xn-x（n-1）=2n则x6=（）；当2/x1+2/x2+2/x3+...+2/xn=2000/1

若规定"!"是数学运算符号,且1!=1,=2x1=2,=3x2x1,…,则100!/98!的值为?若规定"!"是数学运算符号,且1!=1,=2x1=2,=3x2x1,…,则100!/98!的值为?若规

若规定!为一种运算,并且有1!=1,=2x1,=3x2x1,=4x3x2x1,求(n-1)!分之(n+1)!若规定!为一种运算,并且有1!=1,=2x1,=3x2x1,=4x3x2x1,求(n-1)!

1,x1,x2...Xn,成等比数列,x1x2..xn>0,x1*x2*...xn=?x1,x2...Xn,2成等比数列,x1x2..xn>0,x1*x2*...xn=?1,x1,x2...Xn,成等

有一数列x1,x2,x3……xn-1,xn,规定x1=2,x2-x1=4,x3-x2=6……xn-xn-1=2n,则x6=（）.（2）当2/x1+2/x2+2/x3+2/x4+……2/xn的结果是20

（-1x1/2）+(-1/2x1/3)+(-1/3x1/4)+.+(-1/99x1/100)=?（-1x1/2）+(-1/2x1/3)+(-1/3x1/4)+.+(-1/99x1/100)=?（-1x

1x1/2+2x1/3+3x1/4+.+99x1/100=?有谁知道这道题如何解吗1x1/2+2x1/3+3x1/4+.+99x1/100=?有谁知道这道题如何解吗1x1/2+2x1/3+3x1/4+

1/2x1/3+1/3x1/4+1/4x1/5……+1/99x1/100=?1/2x1/3+1/3x1/4+1/4x1/5……+1/99x1/100=?1/2x1/3+1/3x1/4+1/4x1/5…

(X1)^2+(X2)^2=?|X1-X2|=?(X1)^3+(X2)^3=?求公式(X1)^2+(X2)^2=?|X1-X2|=?(X1)^3+(X2)^3=?求公式(X1)^2+(X2)^2=?|

x1,x2>=0,x1+x2=2^x1+2^x2x1,x2>=0,x1+x2=2^x1+2^x2x1,x2>=0,x1+x2=2^x1+2^x2证明:∵x1>=0∴2^x1>=1又∵x1+x2〈=1∴

x1^3-x2^3=(x1-x2)(x1^2+x1x2+x2^2)是怎么算的x1^3-x2^3=(x1-x2)(x1^2+x1x2+x2^2)是怎么算的x1^3-x2^3=(x1-x2)(x1^2+x

线性代数里的r(x1,x2,x3,x1+2x2)=r(x1,x2,x3)?为什么?线性代数里的r(x1,x2,x3,x1+2x2)=r(x1,x2,x3)?为什么?线性代数里的r(x1,x2,x3,x

证明f(x1+x2)+f(x1-x2)=2f(x1)f(x2)为偶函数证明f(x1+x2)+f(x1-x2)=2f(x1)f(x2)为偶函数证明f(x1+x2)+f(x1-x2)=2f(x1)f(x2