Đáp án:

Giải thích các bước giải:

 (Mik ko ghi đề lại nha)

Bài 1:

a/ = 13/3 . 2/5 - 2/5 . 1/3 + 2/5

= 2/5.(13/3 - 1/3 + 1)

= 2/5.(12/3 + 1)

= 2/5.(4 + 1)

= 2/5. 5 = 2

b/ = 100/123. (9/12 + 7/12) + 23/123. (27/15 - 7/15)

= 100/123. 4/3 + 23/123. 4/3

= 4/3. (100/123 + 23/123)

= 4/3. 1 = 4/3

d/ = (3/5 - 7/9 + 7/5 - 2/9) : 83/4

= [(3/5 + 7/5) - (7/9 + 2/9)] : 83/4

= (2 - 1) : 83/4

= 1 : 83/4

= 1. 4/38 = 4/38

e/ = 12^4. 10^2 / 5^4 . 4^5 . 5^2

= (2^2 . 3)^4 . (2 . 5)^2 / 5^6 . (2^2)^5

= 2^8 . 3^4 . 2^2 . 5^2 / 5^6 . 2^10

= 3^4 / 5^4

= 81 / 625  

Câu c mik ko bt lm :<<< Sorry bn :<<<

Bài 2: 

d/ => |x - 5/3| - 1/4 = 3/4

=>  |x - 5/3| = 3/4 + 1/4

=> |x - 5/3| = 1

=> x - 5/3 = 1

=> x = 1 + 5/3

=> x = 3/3 + 5/3

=> x = 8/3

e/ => 2^2x+1 = 2^5

=> 2x + 1 = 5

=> 2x = 5 - 1

=> 2x = 4

=> x = 4 : 2

=> x = 2

c/ => ( x - 1/2)^2 = (3/5)^2 = (-3/5)^2

TH1: x - 1/2 = 3/5

=> x = 3/5 + 1/2

=> x = 6/10 + 5/10

=> x = 11/10

TH2: x - 1/2 = -3/5

=> x = -3/5 + 1/2

=> x = -6/10 + 5/10

=> x = -1/10

a/ -1/4 + 1/4 : x = -5/8

=> 1/4 : x = -5/8 - (-1/4)

=> 1/4 : x = -5/8 + 2/8

=> 1/4 : x = -3/8

=> x = 1/4 : (-3/8)

=> x = 1/4. (-8/3)

=> x = -2/3

b/ => -4/9 + |3x + 1/2| = 2 - 4/9

=> -4/9 + |3x + 1/2| = 18/9 - 4/9 

=> -4/9 + |3x + 1/2| = 14/9

=> |3x + 1/2| = 14/9 - (-4/9)

=> |3x + 1/2| = 14/9 + 4/9

=> |3x + 1/2| = 18/9

=> |3x + 1/2| = 2

=> 3x + 1/2 = 2 

=> 3x = 2 - 1/2

=> 3x = 4/2 - 1/2

=> 3x = 3/2

=> x = 3/2 : 3

=> x = 3/2. 1/3

=> x = 1/2