Tính A/B
A=(14+1/4)(34+1/4)(54+1/4)...........(194+1/4)
B=(24+1/4)(44+1/4)(64+1/4)...........(204+1/4)
A=1+(2)+3+(-4)+...+(-100)+101
B=(-2)+4+(-6)+....+(-98)+100
C=4+(-14)+(-24)+34+44+...+1994+2004
4 + 14 + 24 + 34 + 44 + 54 + 64 + 74 +84 + 94 + 100 = ?
4+14+24+34+44+54+64+74+84+94+100=590
4 + 14 + 24 + 34 + 44 + 54 + 64 + 74 + 84 + 94 + 100 = 590
4 + 14 + 34 + 44 + 54 + 64 + 74 + 84 + 94+ 100 =590
Tính hợp lý:
1, 1+(-4)+7+(-10)+13
2, -2+7+(-12)+17+(-22)
3, 44+45+46+47-24-25-26-27
4, (-213)+186+(-14)+217+54+(-49)
`@` `\text {Ans}`
`\downarrow`
`1,`
\(1+(-4)+7+(-10)+13\)
`= 1+(7+13)+(-4-10)`
`= 1+10-14`
`= 11-14`
`= -3`
`2, `
\(-2+7+(-12)+17+(-22)\)
`= -2+(7+17)+(-12-22)`
`= -2 + 24 - 24`
`= -2`
`3,`
\(44+45+46+47-24-25-26-27\)
`= (44 - 24)+(45 - 25) + (46 - 26)+(47 - 27)`
`= 20 + 20 + 20 + 20`
`= 40`
`4,`
\((-213)+186+(-14)+217+54+(-49)\)
`= (186 + 54)+(-213-14-49) + 217`
`= 240 - 276 + 217`
`= -36 + 217 = 181`
A=\(\dfrac{2}{3}\)+\(\dfrac{14}{15}\)+\(\dfrac{34}{35}\)+\(\dfrac{62}{63}\)+\(\dfrac{98}{99}\)+\(\dfrac{142}{143}\)+\(\dfrac{194}{195}\)
Và B=5+\(\dfrac{1}{2^2}\)+\(\dfrac{1}{3^3}\)+\(^{\dfrac{1}{4^4}}\)+\(\dfrac{1}{5^5}\)+\(\dfrac{1}{6^6}\)+\(\dfrac{1}{7^7}\).So sánh A và B
1. Tính :
a) 23 + 24 - ( 65 x 2 - 4 ) x 4 + 66 + 44 - ( 54 : 9 x 9 : 9 + 45 ) : 1 + 1 - 1 x ( 23 + 23 - 23 x 2 +1 ) = ???
b) 4444444444444444444444444444444444444444444444444444444444444444444 : 1 = ???
c ) 3^0 = ???
d)1/1 = ???
e ) Em hãy tả em =)).
1. Tính:
a) 23 + 24 - ( 65 x 2 - 4 ) x 4 + 66 + 44 - ( 54 : 9 x 9 : 9 + 45 ) : 1 + 1 - 1 x ( 23 + 23 - 23 x 2 +1 ) = 51
b) 4444444444444444444444444444444444444444444444444444444444444444444 : 1
= 4444444444444444444444444444444444444444444444444444444444444444444
c) 30 = 0
d) 1/1 = 1
e)
a) - 530
b) 44444444444444444444444444444444444444444444444444444444444444444444
c) 0
d) 1
e) Em là em
-530
444444444444444444444444444444444444444444444444444444444444444
0
1
...
Bai1 tính nhanh phép tính
a) 37581-9999
Bài2 tính nhanh
a) 36×28+36×82+64×69+64×41
b) A=41×66+34×41/3+7+11+...+79
c) 1×5×6+2×10×12+4×20×24+9×45×54/1×3×5+2×6×10+4×12×20+9×27×45
Bài 1 :
a) 37581 - 9999 = 37581 - 10000 - 1 = 27581 - 1 = 27580
k cho mình nha bạn !
a)37581-9999=37581-(9999+1-1)=37581-(10000+1)=37581-10000-1=27581+1=27582
Tính giá trị biểu thức A = 8 3/17. 5 1/4 +3 14/17 . 5 1/4 / ( 1 14/17 - 1 1/34) . 34
Tính giá trị của biểu thức
a, 1/4 + 1/5 + 3/4 + 2/5
b, 2/7 + 5/14 + 1/7 + 3/14
c, ( 1-1/2) x ( 1 - 1/3 ) x ( 1-1/4 ) x ( 1-1/5 )
d, 1/4 + 1/8 + 1/16 + 1/32 + 1/64 + 1/128
a) -5/9 . 4/13+ -5/9. 9/13+2 và 5/9 ( 2 và 5/9 là hỗn số)
b) (-2)^3. -1/24+( 4/3- 1 và 5/6) : 3/14
c) 200 - (-100) -100+ (-20)
d) 15/34 +7/21 +19/34 -5/15 +3/7
e) (1-1/2) . (1-1/3). (1-1/4).....(1-1/1012)
g) (1/2+1/3-1/4) : 7/24
h) 15^20 . 9^10/ 27^12.25^10