Parameter values for a singular matrix

The matrix (k34k1)\begin{pmatrix} k & 3 \\ 4 & k-1 \end{pmatrix} is singular (non-invertible) for two different real values of kk. What is the sum of those two values?

Show hints (2)+
  1. Singular means det=0\det = 0; here that gives a quadratic in kk.
  2. The sum of the roots of k2k12=0k^2 - k - 12 = 0 is (1)=1-(-1) = 1 (Vieta).

Answer

Reveal answer →

1

Want the full step-by-step worked solution? It's part of Premium - along with a worked solution for every question in the bank.

Asked at: Multi-Strategy Quant, Data-Driven Research

Related questions