रैखिक समीकरण निकाय kx + y + z = 1, x + ky + z = 1 और x + y + kz = 1 का एकमात्र हल होगा, यदि

This question was previously asked in
NDA (Held On: 17 April 2016) Maths Previous Year paper
View all NDA Papers >
  1. k ≠ 1 और k ≠ -2
  2. k ≠ 1 और k ≠ 2
  3. k ≠ -1 और k ≠ -2
  4. k ≠ -1 और k ≠ 2

Answer (Detailed Solution Below)

Option 1 : k ≠ 1 और k ≠ -2
Free
NDA 01/2025: English Subject Test
30 Qs. 120 Marks 30 Mins

Detailed Solution

Download Solution PDF

संकल्पना

माना कि समीकरणों की प्रणाली निम्न है,

a1x + b1y + c1z = d1

a2x + b2y + c2z = d2

a3x + b3y + c3z = d3

⇒ AX = B

⇒ X = A-1 B = 

⇒ यदि det (A) ≠ 0 है, तो प्रणाली विशिष्ट हल वाली संगत प्रणाली है। 

गणना:

रैखिक समीकरण की दी गयी प्रणाली kx + y + z = 1, x + ky + z = 1 और x + y + kz = 1 हैं। 

माना कि A = है। 

det (A) = |A| = k (k2 – 1) – 1(k -1) + 1 (1 – k)

⇒ |A| = k3 – k – k + 1 + 1 – k = k3 – 3k + 2

विशिष्ट हल के लिए,

det (A) ≠ 0

⇒ k3 – 3k + 2 ≠ 0

⇒ (k – 1) (k2 + k - 2) ≠ 0

⇒ (k – 1) (k – 1) (k + 2) ≠ 0

∴ k ≠ 1 और k ≠ -2

Latest NDA Updates

Last updated on Jun 18, 2025

->UPSC has extended the UPSC NDA 2 Registration Date till 20th June 2025.

-> A total of 406 vacancies have been announced for NDA 2 Exam 2025.

->The NDA exam date 2025 has been announced. The written examination will be held on 14th September 2025.

-> The selection process for the NDA exam includes a Written Exam and SSB Interview.

-> Candidates who get successful selection under UPSC NDA will get a salary range between Rs. 15,600 to Rs. 39,100. 

-> Candidates must go through the NDA previous year question paper. Attempting the NDA mock test is also essential. 

More Application of Determinants Questions

More Determinants Questions

Hot Links: teen patti game teen patti club rummy teen patti