a) 56 + 7. (-5) + (-9).(-2)
Tính nhẩm
9 x 5 =
63 : 7 =
8 x 8 =
5 x 7 =
8 x 7 =
3 x 8 =
40 : 5 =
5 x 5 =
7 x 5 =
7 x 8 =
6 x 4 =
45 : 9 =
7 x 7 =
35 : 5 =
56 : 8 =
2 x 8 =
81 : 9 =
9 x 9 =
35 : 7 =
56 : 7 =
9 x 5 = 45
63 : 7 = 9
8 x 8 = 64
5 x 7 = 35
8 x 7 =56
3 x 8 = 24
40 : 5 = 8
5 x 5 = 25
7 x 5 = 35
7 x 8 =56
6 x 4 = 24
45 : 9 = 5
7 x 7 = 49
35 : 5 = 7
56 : 8 = 7
2 x 8 = 16
81 : 9 = 9
9 x 9 = 81
35 : 7 = 5
56 : 7 = 8
ay bạn ơi dễ vậy mà
1) (5¹⁹⁸⁶-5¹⁹⁸⁵) : 5¹⁹⁸⁵
2) (7⁸⁴⁶+7⁸⁴⁷) : 7⁸⁴⁶
3) (9²⁰¹⁸-3⁴⁰³⁶) : 6²⁰⁰⁶
4) (7⁸⁰.8⁷⁰-56⁷⁰) : 56⁷⁰
5) 4⁴⁰¹⁶:(4⁴⁰¹⁷-4⁴⁰¹⁶)
6) (12²⁰⁶.2²⁰⁷-24²⁰⁶) :24²⁰⁶
7) (5²-24)⁸⁹⁴⁶+4³⁰:2⁶⁰
8) (37.8¹⁰⁰⁷-7.2³⁰²¹) :8¹⁰⁰⁷
-Mình cần gấp ạ
1.
$(5^{1986}-5^{1985}):5^{1985}=5^{1985}(5-1):5^{1985}=5-1=4$
2.
\((7^{846}+7^{847}):7^{846}=7^{846}(1+7):7^{846}=1+7=8\)
3.
\((9^{2018}-3^{4036}):6^{2006}=[(3^2)^{2018}-3^{4036}]:6^{2006}\)
$=(3^{4036}-3^{4036}):6^{2006}=0:6^{2006}=0$
4.
$(7^{80}.8^{70}-56^{70}):56^{70}$
$=[7^{10}(7.8)^{70}-56^{70}]:56^{70}$
$=[7^{10}.56^{70}-56^{70}]:56^{70}$
$=56^{70}(7^{10}-1):56^{70}=7^{10}-1$
5.
$4^{4016}:(4^{4017}-4^{4016})=4^{4016}:[4^{4016}(4-1)]$
$=4^{4016}:4^{4016}:3=1:3=\frac{1}{3}$
6.
$(12^{206}.2^{207}-24^{206}):24^{206}$
$=(12^{206}.2^{206}.2-24^{206}):24^{206}$
$=[(12.2)^{206}.2-24^{206}]:24^{206}$
$=(24^{206}.2-24^{206}):24^{206}$
$=24^{206}(2-1):24^{206}=2-1=1$
7.
$(5^2-24)^{8946}+4^{30}:2^{60}=1^{8946}+(2^2)^{30}:2^{60}$
$=1+2^{60}:2^{60}=1+1=2$
8.
$(37.8^{1007}-7.2^{3021}):8^{1007}=[37.8^{1007}-7.(2^3)^{1007}]:8^{1007}$
$=[37.8^{1007}-7.8^{1007}]:8^{1007}$
$=8^{1007}(37-7):8^{1007}=37-7=30$
1.a.-5/9 + 3/5 - 3/9 + -2/5
b.5/17 - 9/15 - 2/17 + -2/5
c.-5/13 - [3/5 + 3/13 - 4/10]
2. a.9/18 - -7/12 + 13/22
b.5/-8 + 14/25 - 6/10
3.62/7 . x =29/9 : 3/56
giải thích hộ mình nha mn.mình cảm ơn mn
Tính :
A= 3/2 - 5/6 +7/12 - 9/20 + 11/30 - 13/42 + 15/56 - 17/72 = 19/70
Tính :
A= 3/2 - 5/6 + 7/12 - 9/20 + 11/30 - 13/42 + 15/56 - 17/72 + 19/70
a) 92/9 + 13/5 - 56/9
b) 58/7 - (31/9 + 30/7)
c) 2/3 + 1/3 x 9/4 - 13/12
d) 41/8 - 7/4 : 11/5
e) 478/19 : 5/4 - 668/19 : 5/4
f) 32/21 x 49/45 : 16/22 x 15/33
g) 2020x2018+9 / 2019x2020-2011.
Giup minh voi minh dang can gap!!!
58/7 - (31/9 + 30/7)
= 58/7 - 31/9 - 30/7
= (58/7 - 30/7) - 31/9
= 28/7- 31/9
= 4 - 31/9 = 36/9 - 31/9
= 5/9
478/19÷(-5/4)-668/19÷(-5/4)
=(478/19-668/19):(-5/4)
=-10 . (-4/5)
=8
Tìm x:
a.62/7*x=29/9:3/56
b.4/5:x=1/5-1/7
c.5x+1/2=2/3
d.1/7-3/5x=3/5
a 1/30+2/42+3/56+....+4/380
b 3-5+7-9+................+143-145+147
a 1/30+2/42+3/56+.....+4/380
b 3-5+7-9+.....+143-145+147
xếp các phân số theo thứ tự lớn đến bé :
a) 25 phần 5 , 5 phần 8 , 21 phần 56 , 7 phần 3 , 25 phần 35
b) 1 phần 5 , 9 phần 7, 9 phần 2 , 25 phần 50 , 2 phần 9
a) \(\frac{25}{5}\); \(\frac{7}{3}\) ; \(\frac{25}{35}\); \(\frac{5}{8}\); \(\frac{21}{56}\)
b) \(\frac{9}{2}\) ; \(\frac{9}{7}\); \(\frac{25}{50}\); \(\frac{2}{9}\); \(\frac{1}{5}\)
k cho mk nha