谁给我出40道 有理数混合运算 要有乘方别太难
谁给我出40道 有理数混合运算 要有乘方别太难
急
[-|98|+76+(-87)]*23[56+(-75)-(7)]-(8+4+3)
5+21*8/2-6-59
68/21-8-11*8+61
-2/9-7/9-56
4.6-(-3/4+1.6-4-3/4)
1/2+3+5/6-7/12
[2/3-4-1/4*(-0.4)]/1/3+2
22+(-4)+(-2)+4*3
-2*8-8*1/2+8/1/8
(2/3+1/2)/(-1/12)*(-12)
(-28)/(-6+4)+(-1)
2/(-2)+0/7-(-8)*(-2)
(1/4-5/6+1/3+2/3)/1/2
18-6/(-3)*(-2)
(5+3/8*8/30/(-2)-3
(-84)/2*(-3)/(-6)
1/2*(-4/15)/2/3
-3x+2y-5x-7y
1.345x0.345x2.96-1.345(的3次方)-1.345x0.345(的2次方)
=-1.345(1.345^2-2*1.345*0.345+0.345^2)
=-1.345(1.345-0.345)^2
=-1.345
1+(-2)+3+(-4)+.+(-1)(的n+1次方)*n
n为奇数
1+(-2)+3+(-4)+.+[(-1)的n+1次方]n
=[1+(-2)]+[3+(-4)]+.+[(-1)的n+1次方]n
=(-1+ -1+...+ )+n
=(1-n)/2+n
=(n+1)/2
n为偶数
1+(-2)+3+(-4)+5+(-6)+.+[(-1)^(n+1)]n
=1+(3-2)+(5-4)+(7-6).+(n-1-(n-2))+(-n)
=n/2-n
=-n/2 (1)7.2-(-5)+83+(-0.7)
(2)8+(-6.45)-42+91
(3)(-20)+(+3)-(-5)-7
(4)(-8)+10+2-57
(5)5.9+8.4-(-78)+(-3.8)
(6)4.8-(-69)+6.5-(-77)
(7)(-8)-61-(31)+(-2.9)
(8)9.3+(-7.2)-(+3)+5.2
(9)(-5)+13-(-5.8)-(-54)
(10)(+13)-9.6+(-20)