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:
99 is 9 times 11 144 divide by 9 is 16
Here the graph and what else you need
Answer:
perimeter: 4x+2 area: x^2+x
Step-by-step explanation:
for perimeter, you add x+x+x+x+1+1, which is 4x+2
for area, you multiply x*x+1, which would be x^2+x
X=4 & y=3
Explanation:
Picture