a) A = 3² . 1/243 . 81² . 1/3²
= 3² . 1/3⁵ . (3⁴)² . 1/3²
= 3² . 1/3⁷ . 3⁸
= 3¹⁰ . 1/3⁷
= 3³
= 27
b) B = (4.2⁵) : (2³ . 1/6)
= (4.32) : (8 . 1/6)
= 128 : 4/3
= 96
c) C = (-1/3)³.(-1/3)².(-1/3)
= (-1/3)³⁺²⁺¹
= (-1/3)⁶
= 1/729
d) D = (-1/3)⁻¹ - (-6/7)⁰ + (1/2)² : 2
= -3 - 1 + 1/4 : 2
= -4 + 1/8
= -31/8
a)(5+1/5-2/9)-(2-1/23-3/35+5/6)-(8+2/7-1/18)
b) 1/3-3/4(-3/5+1/64- -2/9-1/36+1/15
c) -5/7-(-5/67)+13/10+1/2+(-1/6)+1 3/14-(-2/5)
d)3/5:(-1/15-1/6)+3/5:(-1/3-1 1/15)
Bài 1: Thực hiện phép tính
a, (-1/2)^4 - |-2/3| + 2016^0
b, (2/3 - 5/7) (2/7 + 5/21 -1)
c, 6^3 . 27/2^4 . 3^6
Bài 2: chứng minh rằng
A= 3/1^2. 2^2 + 5/2^2 . 3^2 + 7/3^2 . 4^2 + ... + 19/9^2 . 10^2 < 1
Bài 3: tìm x biết
a, -1/2x - 3/5 = -4/5
b, 1-5x/2 = 7x+ 3/9
c, (2x-1)^5 = 243
d, (x+1)^2016 = 1
a) (2x-1)^4=8^1
b) (x-1)^5= -32
c) 2^x +2^x+3=144
d) (2x-1)^6=(2x-1)^8
e) (x-7)^x+3 -(x-7)^x+1=0
Bài 1: Tính
a) -7/9 . 2/3/4 (2/3/4 là hỗn số : 2 là số nguyên, 3/4 là phân số)
b) 2/3 + 1/3 . (-2/5)
c) 3/4 . 15/1/3 - 3/4 . 43/1/3
d) (-49,1) . 13/27 - 58,9 . 13/27
e) 0,375 : (-4,5)
f) 3/1/7 : (-1/3/7)
g) 9/1/3 : 4/2/3 - 2
h) (7/3/4 : 0,3125 + 4,5 . 2/2/45) : (-8,5)
Bài 2: Tính giá trị biểu thức
A = (-6/11) . 7/10 . (11/-6).(-20)
B = (-1/9) . (-17/29) . 58/51
C = (-3/7) . 5/11 + (-5/14) . 5/11
D = (1/1/27 . 12/23 . 9/14) : (-3/23)
Bài 3: Tìm x
a) 3/7 . x - 2/5 . x = -17/35
b) (3/4 . x -9/16) . [1/3 + (-3/5) : x] = 0
c) (x + 3/5) . (x + 1) = 0
A=27/23+5/21-4/23+16/21+1/2
B=6.(-1/3)^3-3.(-1/3)^2.(-1/3)+1
C = 23và1/3(hỗn số):(-5/7)-13 Và 1/3:(-5/7)
D=(-0.75-1/4):(-5)+1/15-(-1/5):(-3)
1. Tính hợp lí:
a) B = 1/2 - [ 3/8 + ( -7/4 ) ]
b) -4/12 - ( -13/39 - 0,25 ) + 0,75
c) 1/2 - 1/3 + 1/23 + 1/6
d) ( -13/7 - 4/9) - ( -10/7 - 4/9 )
e) ( 7/8 - 5/2 + 4/7 ) - ( -3/7 + 1 - 13/8 )
f) -3/7 + ( 3 - 3/4 ) - ( 2,25 - 10/7)
g) ( 5/3 - 3/7 + 9 ) - ( 2 + 5/7 - 2/3 ) + ( 8/7 - 4/3 - 10 )
a)-1/24-[1/4-(1/2-7/8)]
b)(5/7-7/5)-[-1/2-(-2/7-1/10)
c)(-1/2)-(-3/5)+(-1/9)+1/71-(-2/7)+4/35-7/18
d) (3-1/4+2/3) -(5-1/3-6/5)-(6-7/4+3/2)
1)tìm x
a)(1/3-5/6.x)^3+21/54=5/6
b)1/12-1/3(1/2.x-1)^4=1/16
c)(3/5)^x-1+5.(3/5)^x-1=54/25
d)(2/3)^x+(2/3)^x+2=101/243
2) so sánh
a)1/27^11 và 1/81^8
b)1/3^99 và 1/11^21
