Q 41 :

Consider an A.P.: a1,a2,,an; a1>0. If a2-a1=-34,  an=14a1 and i=1nai=5252, then i=117ai is equal to:            [2026]

  • 952

     

  • 136

     

  • 476

     

  • 238

     

(4)

 



Q 42 :

If the sum of the first four terms of an A.P. is 6 and the sum of its first six terms is 4, then the sum of its first twelve terms is           [2026]

  • −20

     

  • −26

     

  • −24

     

  • −22

     

(4)

 



Q 43 :

Let the arithmetic mean of 1a and 1b be 516, a>2. If α is such that a,4,α,b are in A.P., then the equation αx2-ax+2(α-2b)=0 has:  [2026]

  • both roots in the interval (-2,0)

     

  • one root in (0,2) and another in (-4,-2)

     

  • one root in (1,4) and another in (-2,0)

     

  • complex roots of magnitude less than 2

     

(3)

 



Q 44 :

Let a1,a2,a3,a4 be an A.P. of four terms such that each term of the A.P. and its common difference l are integers. If a1+a2+a3+a4=48 and a1a2a3a4+l4=361, then the largest term of the A.P. is equal to              [2026]

  • 23

     

  • 21

     

  • 24

     

  • 27

     

(4)

 



Q 45 :

The common difference of the A.P. a1,a2,,am is 13 more than the common difference of the A.P. b1,b2,,bn. If b31=-277, b43=-385 and a78=327, then a1 is equal to  [2026]

  • 21

     

  • 16

  • 24

     

  • 19

     

(4)