Question

Matematica clasa a 9 a ....am nevoie urgent....va rog...6...7...8...si 9....ce puteti...macar un exercitiu​

Answer 1

Răspuns:

Explicație pas cu pas:

6.

a)

2/x/ ≤ 8

/x/ ≤ 4

x = [-4, 4]

_________

b)

-6 < 2x - 3 < 6

-3 < 2x < 9

-3/2 < x < 9/2

x = (-3/2, 9/2)

__________

c)

-√2 ≤ x + 2 ≤ √2

-√2 - 2 ≤ x ≤ √2 + 2  

[-√2 - 2, √2 + 2]

_______________

7.

-5 ≤ (7x + 4)/2 < 16

-10 ≤ 7x + 4 < 32

-14 ≤ 7x < 28

-2 ≤ x < 4

A = [-2, 4)

-8 ≤ 5x - 2 ≤ 8

-6 ≤ 5x ≤ 10

-6/5 ≤ x ≤ 2

B = [-6/5, 2]

A U B = [-2, 4)

A ∩ B =  [-6/5, 2]

A ∩ Z = {-2, -1, 0, 1, 2, 3}

B ∩ N = {0, 1, 2}

_______________

9.

/x/ > 3

A = (-∞, -3) U (3, + ∞)

____

/x + 1/ > 2

B = (- ∞, -3) U (1, + ∞)

_____

/x/ ≤ 0

C = {0}