Can anyone help me with question no 11
Attachments:
Answers
Answered by
1
Step-by-step explanation:
tn = Sn - S(n - 1)
tn = 3(4ⁿ - 1) - 3(4ⁿ⁻¹- 1)
=> 3*4ⁿ - 3 - [3*4ⁿ⁻¹ - 3 ]
=> 3*4ⁿ - 3 - 3*4ⁿ⁻¹ + 3
=> 3*4ⁿ - 3*4ⁿ⁻¹
=> 3*4ⁿ - 3*4ⁿ*4⁻¹
=> 3*4ⁿ [1 - 1/4]
=> 3*4ⁿ*3/4
=> 3*4ⁿ*3 * 1/4
=> 3*3*4ⁿ*4⁻¹
=> 9(4ⁿ⁻¹) => option D
Similar questions