2/9-x=-5/9
=>x=2/9+5/9=7/9
\(\dfrac{2}{9}-x=\dfrac{-5}{9}\)
x = \(\dfrac{2}{9}+\dfrac{5}{9}\)
x = \(\dfrac{7}{9}\)
Tính A= 5 x 4^15 x 9^9 - 4 x 3^20 x 8^9 : 5 x 2^9 x 6^19 - 7 x 2^29 x 27^6
a)2/9-(-4/9)=
b)(-1/24+0,25+1 1/12):(-1/2)2
c)3/13.-5/9+10/13.-5/9+-4/9
Bài 2:
a)-4 1/5:x=5 1/4, b)7/12-5/12.x=1/12
tim x
a, 3^x=3^2*9
b, (21+x):9=9^5:9^4
c, 5^x-1-13=613
a, x+2=-9-11
b, x-2=-6+17
c,2x+5=-9+18
d, x+9=2-17
e, /x-5/=5
g,/x-5/=/-5/
h, (x-7)(x+8)=0 i, /x-2/=/-72/
Tính :
a) 13/15 + 4/7 - 101/105 b) 2/5 + 3/5 + x 4/9 c) 3/4 x 5/2 x 7/6
d) 1/2 : 1/4 - 2/9 e) 2/3 - 1/4 +2/9 g) 5/2 + 1/3 x 3/2
Tìm x ∈ Z, biết:
a) x + 5 = -2 + 11
b) -3x = -5 + 29
c) | x | - 9 = -2 + 17
d) | x – 9 | = -2 + 17
1. -2/9 x 15/17 + -2/9 x 2/17
2. -5/3 x 6/5 + -7/9 x 3/10
3. 15/20 x 7/5 + -9/7 x -6/4
4.-25/13 x 5/19 + -25/13 x 14/19
5 -7/13 x 13/5 + -9/7 x 5/3
6. 27/35 x 5/9 - 2/7 x -7/5
7. 10/13 x 13/5 + {-9/5} x 10/3
8. 100/27 x 9/20 + 40% x 5/3
9. 1,5 x 5/12 + 1/4 x 3/4
10. 2 1/2 x 7/5 + {-9/10} x 2/3
11. X + 45% = 2 1/2 -5/3
12. 80% + X = -5/2 + 3/4
13. 4/25 - X =-5/2 + -3/10
Tính:
a) 2^5 x 13^12 x 7^8 : 27 x 13^10 x 7^9
b) 2^n x 11 x 3 : 6^n x 3
c) 5^5 x 7 x 9^5 : 15^10
d) 7 x 8^10 x 27^9 - 8 x 9^13 x 2^27 : 7 x 6^26 x 2^2 - 2^4 x 8^3 x 27^9
e) 2^2^1^2015
f) 2015^0^2015^0^2015
Bài 1 : So sánh
a, 3^21 và 2^31
b, 2017^10 + 2017^9 và 2018^10
Bài 2 : Cho A = 5 × 4^15 x 9^9 - 4 x 3^20 x 8^9
và B = 5 × 2^9 x 6^19 - 7 × 2^20 x 27^6
Tính A : B .
