Tính
1) (- 2) . (- 7) . (- 5) 2) 15 – 22 + ( - 17)
3) 25. (- 4) – 20. (- 5) 4) 185 – (49 + 185)
5) ( -19 ) . (- 13) + 13 . (-29)
6)79 . 23 + 21 . 23 7) 2. ( 6 . 42 – 85 : 5)
8) (-5) .8 . (-2) . 3 9) 200 +32 –( 50 +32 )
10) 3 . (-2)2 + 4 . (-5) +20
TÝnh
1) (- 2) . (- 7) . (- 5) 2) 15 – 22 + ( - 17)
3) 25. (- 4) – 20. (- 5) 4) 185 – (49 + 185)
5) ( -19 ) . (- 13) + 13 . (-29)
6)79 . 23 + 21 . 23 7) 2. ( 6 . 42 – 85 : 5)
8) (-5) .8 . (-2) . 3 9) 200 +32 –( 50 +32 )
10) 3 . (-2)2 + 4 . (-5) +20
tính:
a) (-2) . (-7) . (-5)
b) 15 - 22 + (-17)
c)25. (- 4) – 20. (- 5)
d) 185 – (49 + 185)
e) ( -19 ) . (- 13) + 13 . (-29)
1. Tính
a, 1+7+8+15+23+...+160
b, 17+4+5+9+19+...+60+9
c, 78*3+78*24+78*17*22*72
d, 53*39+47*39+47-53*21-47*21
e, 2*53*12+4*6*87-3*8*40
g, 5*7*77-7*60+49*25-15*42
h, 1*2+2*3+3*4+...+2016*2017
Bài 1: Tìm x , biết:
1) x - 2 = -6 12) 3 . | x - 1 | - 5 = 7
2) -5 . x - ( -3 ) = 13 13) -12 . ( x - 5 ) + 7 . ( 3 - x ) = 5
3) 15 - ( x - 7 ) = -21 14) ( x - 2 ) . ( x + 4 ) = 0
4) 3 .x + 17 = 2 15) ( x - 2 ) . ( x + 15 ) = 0
5) 45 - ( x - 9 ) = -35 16) ( 7 - x ) . ( x + 19 ) = 0
6) ( -5 ) + x = 15 17) -5 < x < 1
7) 2 . x - ( -17 ) = 15 18) | x | < 3
8) | x - 2 | = 3 19) ( x - 3 ) . ( x - 5 ) < 0
9) | x - 3 | - 7 = 13 20) 2 . x2 - 3 = 29
10) 72 - 3 . | x + 1 | = 9 21) -6 . x - ( -7) = 25
11) 17 - ( 43 - | x | ) = 45 22) 46 =- ( x - 11 ) = -48
Bài 1: Tính hợp lý
a, 1+2+3+4+............+2005+2006
b, 5+10+15+...........+2000+2005
c, 140+136+132+............+64+60
Bài 2: Thực hiện phép tính
1. (-3).5-(-4).6+(-23)
2. -17 -(-5).6+(12-17)2
3. 15.(-6) + (-6).85- 15.11
4. (-32) - 2.[23.(-3)-(-5 -7).3]
5. 74.(-41)-41.26+(-2)3. [49+(-2)2]
6. -8. (21-13+72)+80. (-21+76-132)
7. [15:(-3)+40:(-8)] -3.(16:8)
8. [-15:(-3)] -3.[2.(-5-9:3)]
a) 79 . 23 + 21 . 23
b) 2. ( 6 . 42 – 85 : 5)
c) (-5) .8 . (-2) . 3
d) 200 +32 –( 50 +32 )
e) 3 . (-2)2 + 4 . (-5) +20
Bài 1: Tính
a, 16/15. -5/4. 54/24. 56/21
b, -5/8 . -12/29 . 8/-10 . 29/5
Bài 2: Tính nhanh giá trị của các biểu thức sau:
a, 4.11 . 3/4 . 9/121
b, -7/25 . 39/ -17 . 50/78
c, 3/7. 2/5 . 7/3. 20 . 19/42
Bài 1: Tính
a, (4/1/9+3/1/4). 2/1/4+2/3/4
b, 9/23. 5/8+ 9/23. 3/8 - 9/23
c, 1+ (9/10 - 4/5) : 3/1/6
d, (-7+/13/) - (13- / -7/ -25) - (25 +/- 10/ -9)