Answer:
cos x ≠ 0 ⇔ x ≠
; k ∈ N

<=> cos²x + sin²x = 1
⇔ 1 = 1
=> x = { R \ (pi/2 + k.pi); k ∈ N}
Step-by-step explanation:
Answer:
B) Aluminum and steel are good conductors of electricity.
Step-by-step explanation:
Answer:
Step-by-step explanation:
Answer: 5, 6
Step-by-step explanation:
0 + 2 = 2
2 , 0
0 + 6 = 6
2, 6
2 + 3 = 5
5, 6
X + 12 = 13
x = 13 - 12
x = 1
The only solution is x = 1
letter B