Solution :
We have to prove that 
(De-Morgan's law)
Let 
then 
and 
and so 
and 
.
Thus, 
and so 
Hence, 
.........(1)
Now we will show that 
Let ⇒
Thus x is present neither in the set A nor in the set B, so by definition of the union of the sets, by definition of the complement.
and 
Therefore, 
and we have .............(2)
From (1) and (2),
Hence proved.
Answer: 65%, 195 children
Step-by-step explanation: To get this, we just do 100-35 to get 65 percent. We can calculate this further, and do 300*0.65, and we get 195. Thus, there were 195 children.
Evaluate A² for A = -3.
(-3)² = (-3) * (-3) = 9
Your answer is 9.
If the question is, however, evaluate A2, which is 2A, for A = -3, then the answer is:
2A = 2(-3) = -6.
