Question

let sets a and b be defined as follows.
a is the set of integers greater than -9 and less than -1
b = {h, l, r, t, v, y}
(a) find the cardinalities of a and b.
n(a) = 7 n(b) = 5

Explanation:

Step1: List integers in set A

Integers: $-8, -7, -6, -5, -4, -3, -2$

Step2: Count elements in A

Count: $7$ elements, so $n(A)=7$

Step3: Count elements in set B

Elements: $h, l, r, t, v, y$ → $5$ elements, so $n(B)=5$

Answer:

$n(A) = 7$, $n(B) = 5$