Q1. Which of the following statements are true and which are false? Justify your answer with a short proof or a counterexample.
- i)) The function f: R → R defined by f(x) = cosx is 1-1. (100 words)
- ii)) The operation * defined by x* y = log(xy) is a binary operation on S, where S is the set {x ∈ R|x > 0}. (100 words)
- iii)) The set {(x1.x2,...,xn) | X1,X2,...,xn ∈ R, x1 = 2x2 + 3} is a subspace of Rn. (100 words)
- iv)) There is no 7 × 5 matrix of rank 6. (100 words)
- v)) If V and V' are vector spaces and T : V → V' is a linear transformation, then whenever u1,u2, ..., uk are linearly independent, Tu₁, Tu2, ..., Tuk are also linearly independent. (100 words)
- vi)) If V is a vector space and T : V → V is a linear operator with det(T) = 0, then T is not diagonalisable. (100 words)
- vii)) The degree of the minimal polynomial of a 3 × 3 matrix is at most 2. (100 words)
- viii)) For any 2 × 2 matrix A, Adj (A') = (Adj(A))'. (100 words)
- ix)) The only matrix which is both symmetric and skew-symmetric is the zero matrix. (100 words)
- x)) There is no co-ordinate transformation that transforms the quadratic form x² + y² + z² to the quadratic form xz + yz. (100 words)
- Cosine function is not 1-1 due to its periodic nature.
- Binary operations require closure: results must stay within the set.
- Subspaces must contain the zero vector; otherwise, they are not subspaces.
- Matrix rank is limited by `min(rows, columns)`; a `7x5` matrix cannot have rank 6.
Answer: This document comprehensively addresses ten statements related to linear algebra concepts from the MTE-02 course. For each statement, its truthfulness is assessed, followed by a detailed justification involving either a short proof or a counterexample. The explanations are designed to align with typical IGNOU course content, covering fundamental definitions, properties of functions, vector spaces, matrices, linear transformations, and quadratic forms. Each sub-question is treated independently ...