<h3>Given</h3>
- Set A: A = {-26, -25, -24, -23, - 22, - 21}
- Set B: B ∈ {x: x is even, x ≥ 6 and x ≤ 20}
<h3>(a) </h3>
<em />
<em>Cardinality means the number of elements in the set.</em>
Cardinality of the set A:
n(A) = 6, since we can count 6 elements.
Set B has even numbers between 6 and 20, both included:
- B = {6, 8, 10, 12, 14, 16, 18, 20}
Then its cardinality is:
<h3>(b) </h3>
To solve this we need to compare the elements of sets A or B with numbers given:
- -22 ∈ A, True ⇒ -22 is listed as element of A
- 6 ∈ B, True ⇒ 6 is listed as element of B
- - 21 ∉ A, False ⇒ - 21 is listed as element of A
- 2 ∈ B, False ⇒ 2 is not listed as element of B
Answer:
Imagine an easier version of this problem: You have a board 5 feet long that you must cut (divide, right?) into two equal parts. It is probably clear to you that you simply divide the length (5) by the number of parts you're dividing it into (2) to obtain the length of each piece (2.5 feet).
Use the same method for your problem 5 feet divided by 6 is 0.83 feet per piece.
We do not ordinarily divide feet into decimal portions, but instead into inches. Since an inch is 1/12 of a foot, you could simply say 5/6 = how many twelfths? or 5/6 = n/12 Solve this by inspection or by cross multiplying 5 times 12 equals n times 6. So n must equal 10, and your pieces of board are each 10 inches long.
Answer is C
hope this helps!
Answer:
[-5, 4) ∪ (4, ∞)
Step-by-step explanation:
Given functions:
Composite function:
![\begin{aligned}(f\:o\:g)(x)&=f[g(x)]\\ & =\dfrac{1}{\sqrt{x+5}-3} \end{aligned}](https://tex.z-dn.net/?f=%5Cbegin%7Baligned%7D%28f%5C%3Ao%5C%3Ag%29%28x%29%26%3Df%5Bg%28x%29%5D%5C%5C%20%26%20%3D%5Cdfrac%7B1%7D%7B%5Csqrt%7Bx%2B5%7D-3%7D%20%5Cend%7Baligned%7D)
Domain: input values (x-values)
For 
to be defined:
Therefore, 
and 
⇒ [-5, 4) ∪ (4, ∞)
(20 + 12) - 8, since the question states n is EIGHT less than the sum of 20 and 12.
