If A= {a, b, c, d} then number of subsets of A are
- 8
- 12
- 16
- 20
The Correct Option is C
Solution and Explanation
To solve the problem, we need to find the number of subsets of the set \( A = \{a, b, c, d\} \).
1. Understanding the Formula for Subsets:
If a set has \( n \) elements, then the total number of subsets is given by:
\( \text{Number of subsets} = 2^n \)
2. Count the Elements in the Set:
The set \( A = \{a, b, c, d\} \) has 4 elements. So, \( n = 4 \).
3. Apply the Formula:
Substitute \( n = 4 \) into the formula:
\( \text{Number of subsets} = 2^4 = 16 \)
Final Answer:
The number of subsets of set \( A \) is \( 16 \).
Top Questions on Subsets
Consider the following subsets of the Euclidean space \( \mathbb{R}^4 \):
\( S = \{ (x_1, x_2, x_3, x_4) \in \mathbb{R}^4 : x_1^2 + x_2^2 + x_3^2 - x_4^2 = 0 \} \),
\( T = \{ (x_1, x_2, x_3, x_4) \in \mathbb{R}^4 : x_1^2 + x_2^2 + x_3^2 - x_4^2 = 1 \} \),
\( U = \{ (x_1, x_2, x_3, x_4) \in \mathbb{R}^4 : x_1^2 + x_2^2 + x_3^2 - x_4^2 = -1 \} \).
Then, which one of the following is TRUE?Let the functions \( f: \mathbb{R} \to \mathbb{R} \) and \( g: \mathbb{R}^2 \to \mathbb{R} \) be given by \[ f(x_1, x_2) = x_1^2 + x_2^2 - 2x_1x_2, \quad g(x_1, x_2) = 2x_1^2 + 2x_2^2 - x_1x_2. \] Consider the following statements:
S1: For every compact subset \( K \) of \( \mathbb{R} \), \( f^{-1}(K) \) is compact.
S2: For every compact subset \( K \) of \( \mathbb{R} \), \( g^{-1}(K) \) is compact. Then, which one of the following is correct?- In the following, all subsets of Euclidean spaces are considered with the respective subspace topologies. Define an equivalence relation \( \sim \) on the sphere \[ S = \left\{ (x_1, x_2, x_3) \in \mathbb{R}^3 : x_1^2 + x_2^2 + x_3^2 = 1 \right\} \] by \( (x_1, x_2, x_3) \sim (y_1, y_2, y_3) \) if \( x_3 = y_3 \), for \( (x_1, x_2, x_3), (y_1, y_2, y_3) \in S \). Let \( [x_1, x_2, x_3] \) denote the equivalence class of \( (x_1, x_2, x_3) \), and let \( X \) denote the set of all such equivalence classes. Let \( L : S \to X \) be given by \[ L\left( (x_1, x_2, x_3) \right) = [x_1, x_2, x_3]. \] If \( X \) is provided with the quotient topology induced by the map \( L \), then which one of the following is TRUE?
- Let \( X \) be an uncountable set. Let the topology on \( X \) be defined by declaring a subset \( U \subset X \) to be open if \( X - U \) is either empty or finite or countable, and the empty set to be open. Then, which of the following is/are TRUE?
- All rings considered below are assumed to be associative and commutative with \( 1 \neq 0 \). Further, all ring homomorphisms map 1 to 1.
Consider the following statements about such a ring \( R \):
P1: \( R \) is isomorphic to the product of two rings \( R_1 \) and \( R_2 \).
P2: \( \exists r_1, r_2 \in R \) such that \( r_1^2 = r_1 \neq 0 \), \( r_2^2 = 0 \), and \( r_1 + r_2 = 1 \).
P3: \( R \) has ideals \( I_1, I_2 \subset R \) with \( R \neq I_1 \), \( (0) \neq I_2 \), and \( R = I_1 + I_2 \) and \( I_1 \cap I_2 = (0) \).
P4: \( \exists a, b \in R \) with \( a \neq 0 \), \( b \neq 0 \) such that \( ab = 0 \).
Then, which of the following is/are TRUE?
Questions Asked in TS POLYCET exam
- The number of elements present in the fifth period of the modern periodic table:
- TS POLYCET - 2025
- Modern Periodic Law And The Present Form Of The Periodic Table
- The volume of CO\(_2\) liberated in litres at STP when 25 g of CaCO\(_3\) is treated with dilute HCl containing 14.6 g of HCl is:
- TS POLYCET - 2025
- Chemical Reactions
- Which one of the following processes involves chemical change?
- TS POLYCET - 2025
- Chemical Reactions
- If \( A \) is the set of odd numbers less than 6 and \( B \) is the set of prime factors of 30, then:
- TS POLYCET - 2025
- Magnetic Field
- If \( A = \{1, 2, 3, 4, 5\} \) and \( B = \{1, 3, 5, 7\} \), then \( n(A \cap B) = \dots \):
- TS POLYCET - 2025
- Magnetic Field