Set theory is the mathematical theory of well-determined collections, called sets, of objects that are called members, or elements, of the set. ... The axioms of set theory imply the existence of a set-theoretic universe so rich that all mathematical objects can be construed as sets
For example, if A = {1, 2, 3} and B = {1, 2, 3, 4, 5} then A Í B (Í means is a subset of). If A = {1, 2, 4, 8}, then n(A) = 4. This is because n(A) means the number of members in set A. The universal set is the set of all sets.
Answer:
The fifth term is -4
Step-by-step explanation:
The sequence has a common difference therefore, it is an arithmetic sequence
The formula for arithmetic sequence is
<em>where,</em>
<em>an is the nth term,</em>
<em>a1 is the first term,</em>
<em>n is the term number and</em>
<em>d is the common difference</em>
<u>Find the 5th term.</u>
an = a1 + ( n-1 ) d
a5 = 20 + ( 5-1 ) -6
a5 = 20+ ( -24 )
a5 = -4
<u>Answer-</u>
<em>After 76 swings</em><em> the angle through which it swings less than 1°</em>
<u>Solution-</u>
From the question,
Angle of the first of swing = 30° and then each succeeding oscillation is through 95% of the angle of the one before it.
So the angle of the second swing =
Then the angle of third swing =
So, this follows a Geometric Progression.
a = The initial term = 30
r = Common ratio =
As we have to find the number swings when the angle swept by the pendulum is less than 1°.
So we have the nth number is the series as 1, applying the formula
Putting the values,
Taking logarithm of both sides,
Therefore, after 76 swings the angle through which it swings less than 1°