会做的做1.如果三角+三角=◎,O=口+口,三角=O+O+O+O,则◎除口=( )A.2 B.4 C.8 D.162.对

1个回答

  • 1.

    D

    2.

    8★6

    =(8*6)/(8-6)

    =48/2

    =24

    3.

    1/36÷(1/4+1/12-7/18-1/36)+(1/4+1/12-7/18-1/36)÷1/36

    =36/36*[1/36÷(1/4+1/12-7/18-1/36)]

    +36/36*(1/4+1/12-7/18-1/36)÷1/36

    =36*1/36÷[36*(1/4+1/12-7/18-1/36)]

    +36*(1/4+1/12-7/18-1/36)÷[36*1/36]

    =1÷[9+3-14-1]+(9+3-14-1)÷1

    =1÷(-3)-3

    =-1/3-3

    =-10/3

    4.

    n为正整数,则(-1)2n次方=(1);(-1)2n+1次方=(-1)

    5.

    a^2=16

    a=±4

    b^2=9

    b=±3

    当a=4,b=3时a-b=4-3=1

    当a=4,b=-3时a-b=4-(-3)=4+3=7

    当a=-4,b=-3时a-b=-4-(-3)=-4+3=-1

    当a=-4,b=3时a-b=-4-3=-7

    6.

    x2次方=(-2)2次方

    x=±2

    y3次方=-1

    y=-1

    当x=2,y=-1时

    x*y^2010

    =2*(-1)^2010

    =2*1

    =2

    当x=-2,y=-1时

    x*y^2010

    =-2*(-1)^2010

    =-2*1

    =-2

    当x=-2,y=-1时

    x^3/y^2009

    =(-2)^3/(-1)^2009

    =-8/(-1)

    =8

    当x=2,y=-1时

    x^3/y^2009

    =2^3/(-1)^2009

    =8/(-1)

    =-8

    7.

    若(a-1)2次方+5取最小值,则a=(-5 )

    8.

    若|a|=2,则a2次方=(4),a3次方=(±8)