41-2^×+1=9
2+9+5+52+41+61+1+41+1+5=
1) \(\dfrac{5}{13}\) +\(\dfrac{-5}{17}\) + \(\dfrac{-20}{41}\) + \(\dfrac{8}{13}\) +\(\dfrac{-21}{41}\)
2) \(\dfrac{1}{5}\) + \(\dfrac{-2}{9}\) + \(\dfrac{-7}{9}\) + \(\dfrac{4}{5}\) +\(\dfrac{16}{17}\)
3) \(\dfrac{2}{3.5}\) + \(\dfrac{2}{5.7}\) +\(\dfrac{2}{7.9}\) +....................+ \(\dfrac{2}{99.101}\)
1: =5/13+8/13-20/41-21/41-5/17
=1-1-5/17=-5/17
2: =1/5+4/5-2/9-7/9+16/17
=16/17+1-1=16/17
3: =1/3-1/5+1/5-1/7+...+1/99-1/101
=1/3-1/101
=98/303
Thực hiện các phép tính sau ( tính hợp lí nếu có thể):
a,2/9-(1/20+2/9) b,-3/14+2/13+(-25)/14+(-15)/13
c,(-3/11)+11/8-3/8+(-8/11) d, 3/8+(-1)/4-(7/12-1/6)
e, (1/3+12/67+13/41)-(79/67-28/41)
a) 2/9 - (1/20 + 2/9)
= 2/9 - 1/20 - 2/9
= (2/9 - 2/9) - 1/20
= 0 - 1/20
= -1/20
b) -3/14 + 2/13 + (-25/14) + (-15/13)
= (-3/14 - 25/14) + (2/13 - 15/13)
= -2 - 1
= -3
c) -3/11 + 11/8 - 3/8 + (-8/11)
= (-3/11 - 8/11) + (11/8 - 3/8)
= -1 + 1
= 0
d) 3/8 + (-1/4) - (7/12 - 1/6)
= 1/8 - 5/12
= -7/24
e) (1/3 + 12/67 + 13/41) - (79/67 - 28/41)
= 1/3 + 12/67 + 13/41 - 79/67 + 28/41
= 1/3 + (12/67 - 79/67) + (13/41 + 28/41)
= 1/3 - 1 + 1
= 1/3
thực hiện phép tính :
a, -1/2 + 19/23+ -9/2+ 4/23 +3 /-6
b. 5/13+ -5/7 +-20/41 + 8/13 +-21/41
c.-5/7 x 19/41 + 5/7 x -21/41 + 5/7
d. 7/3 +1/2 - -3/70
Đây là phân số
L = 3/21 + 3/41 - 3/61 / 9/21 + 9/41 - 9/61 - 11/35 - 11/10 - 11/23 / 2/35 - 2/10 - 2/23
S=2^1+2^2+... +2^8+2^9 chia hết cho -41
1. a) \(\dfrac{5}{3}\) . \(\dfrac{11}{7}\) - \(\dfrac{5}{7}\) . \(\dfrac{5}{3}\)
b) (0,125)\(^{16}\). (-8)\(^{16}\)
c) \(\dfrac{9^2.9^3}{3^9}\)
d) \(\dfrac{9}{24}\) - \(\dfrac{7}{41}\) + \(\dfrac{15}{24}\) + 0,75 - \(\dfrac{34}{41}\)
e) \(5\dfrac{2}{7}\) . ( \(-\dfrac{1}{3}\)) - \(2\dfrac{2}{7}\) . (\(-\dfrac{1}{3}\))
2. a) \(\dfrac{3}{4}\) + \(\dfrac{2}{3}x\) = \(\dfrac{1}{2}\)
b) (2x - 1)\(^2\) = 25
c) | x + 5 | - 6 = 9
1.
a)10/7
b) 1
c) 3
d) 3/4
e) -1
2.
a)-3/8
b)x= 3 và x=-2
c)x=10 và x=-20
bài 1:
7 5/9+15/41+0,6-5/9+26/41
CHO D 9 ^1 +9^ 2+ 9^ 3+ ...+ 9^ 2019+ 9^ 2020
CHỨNG TỎ RẰNG D LÀ BỘI CỦA 41
GIÚP MÌNH NHANH NHÉ
MÌNH ĐANG THI
nếu là thi thì bạn tự làm đi nhé
giải hộ mình nha
1
a, 16 . ( 38 - 2 ) - 38 . ( 16 - 1 )
b, ( - 41 ) . ( 59 + 2 ) + 59 . ( 41 - 2 )
c, 19 . 25 + 9 . 95 + 38 . 15
d,( - 32 ) . 125 . ( -9 ) . ( - 25 )
trả lời nhanh nha
a,6
b,-200
c,1900
d,-900000
k mình nha
mình cần gấp
16 . ( 38 - 2 ) - 38 . ( 16 - 1 )
=16 . 38 - 2 .16 - 38 .16 - 1.38
=16.38.(2.16-1.38)
=608.(32-38)
=608.(-6)
=-3648
1 a, 16.38-16.2-38.16-38.1=608-32-608-38=-70 t