ISRO Electronics & Communication (ECE) 2017 - Question 62

All ISRO Electronics & Communication (ECE) papers | ISRO Electronics & Communication (ECE) 2017

Topic: Engineering Mathematics

Find the Eigen values in the system $\begin{bmatrix}4 & 1 \\ 3 & 2\end{bmatrix} \begin{bmatrix}x \\ y\end{bmatrix} = \lambda \begin{bmatrix}x \\ y\end{bmatrix}$

  • A. 1 and 5
  • B. 4 and 3
  • C. 1 and 2
  • D. 2 and 4

Answer: A. 1 and 5

Explanation: The characteristic equation is $|A - \lambda I| = 0$. This gives $(4-\lambda)(2-\lambda) - 3 = 0$. Expanding this, we get $\lambda² - 6\lambda + 8 - 3 = 0$, which simplifies to $\lambda² - 6\lambda + 5 = 0$. Factoring gives $(\lambda-5)(\lambda-1)=0$, so the eigenvalues are $\lambda = 1, 5$.

| | All questions of ISRO Electronics & Communication (ECE) 2017