Given that A = [8(α β γ -α )] and A 2 = 3I, then :

(a) 1 + 𝛼 2 + 𝛽𝛾 = 0  (b) 1 − 𝛼 2 − 𝛽𝛾 = 0

(c) 3 − 𝛼 2 − 𝛽𝛾 = 0  (d) 3 + 𝛼 2 + 𝛽𝛾 = 0

Slide104.JPG

Advertisement

Slide105.JPG

Advertisement

  1. Class 12
  2. Solutions of Sample Papers and Past Year Papers - for Class 12 Boards

Transcript

Question 40 Given that A = [β– 8(𝛼&𝛽@𝛾&βˆ’π›Ό )] and A2 = 3I, then : a) 1 + 𝛼2 + 𝛽𝛾 = 0 b) 1 βˆ’ 𝛼2 βˆ’ 𝛽𝛾 = 0 c) 3 βˆ’ 𝛼2 βˆ’ 𝛽𝛾 = 0 d) 3 + 𝛼2 + 𝛽𝛾 = 0 Given A2 = 3I [β– 8(𝛼&𝛽@𝛾&βˆ’π›Ό)] [β– 8(𝛼&𝛽@𝛾&βˆ’π›Ό)] = 3I [β– 8(𝛼(𝛼)+𝛽(𝛾)&𝛼(𝛽)+𝛽(βˆ’π›Ό)@𝛾(𝛼)+(βˆ’π›Ό)𝛾&𝛾(𝛽)+(βˆ’π›Ό)(βˆ’π›Ό))] = 3 [β– 8(1&0@0&1)] [β– 8(𝜢^𝟐+𝜷𝜸&𝟎@𝟎&𝜢^𝟐+𝜷𝜸)] = [β– 8(πŸ‘&𝟎@𝟎&πŸ‘)] Thus, 𝜢^𝟐•7+𝜷𝜸 = 3 0 = 3 βˆ’ 𝛼^2βˆ’π›½π›Ύ 3 βˆ’ 𝛼2 βˆ’ 𝛽𝛾 = 0 So, the correct answer is (C)

About the Author

Davneet Singh's photo - Teacher, Engineer, Marketer
Davneet Singh
Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 10 years. He provides courses for Maths and Science at Teachoo.