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Question

If A2 + B2 + C2 = 0, then what is the value of the following?

\(\Delta = \begin{vmatrix} 1 & \cos C & \cos B \\\ \cos C & 1 & \cos A \\\ \cos B & \cos A & 1 \end{vmatrix}\)

This question was previously asked in
NDA 2 2025 GAT Question Paper (14-Sep-2025)
The correct answer is

1

From the matrix equation, the given values simplify to cosA = cosB = cosC = 1, which leads to value = 1.

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Important Questions from Complex Numbers

  1. Consider the following complex numbers
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  3. What is the real part of the number \(15 + 2i\)
  4. What is the real part of the number $5i$?
  5. What is the value of $(6 + 3i) + (2 + 5i)$?
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