KCET2020MathematicsLimits
If a₁ a₂ a₃ a₉ are in AP , then the value of | array lll a₁ & a₂ & a₃ a₄ & a₅ & a₆ a₇ & a₈ & a₉ array | is
Options
- A9 2 (a₁+a₉ )
- B(a₁+a₉ )
- C_ e ( _ e e )
- D1
Correct answer
C. _ e ( _ e e )
Step-by-step solution
a₁, a₂, a₃, , a₉ are in AP. | array lll a₁ & a₂ & a₃ a₄ & a₅ & a₆ a₇ & a₈ & a₉ array | Apply R₁ R₁+R₂-2 R₂ | array ccc a₁+a₇-2 a₄ & a₂+a₈-2 a₅ & a₃+a₉-2 a₆ a₄ & a₅ & a₆ a₇ & a₈ & a₉ array | | array ccc 0 & 0 & 0 a₄ & a₅ & a₆ a₇ & a₈ & a₉ array | aligned & [ a₁+a₇-2 a₄=a₁+a₁+6 d-2 a₁-6 d=0 . & Similarly .a₂+a₄-2 a₅=0, a₃+a₉-2 a₆=0 ] &=0 &= _ e 1= _ e ( _ e e ) aligned