Skip to content
MathsGenie logo
Quick links
Open app

Course home

  1. A Level
  2. Maths AQA
  3. Question bank

1.7.2 Types of sequence (A-level only)

EasyMedium
12345678910111213141516171819202122232425
Question 17

The electrical current InI_nIn​, measured in milliamperes, flowing through a logic gate is monitored at discrete clock cycles. The sequence of current values is defined by the recurrence relation

I1=0.4andIn+1=12Infor n≥1 I_1 = 0.4 \quad \text{and} \quad I_{n+1} = \frac{1}{2I_n} \quad \text{for } n \ge 1 I1​=0.4andIn+1​=2In​1​for n≥1
a.

Find the values of I2I_2I2​, I3I_3I3​ and I4I_4I4​.

[3]
b.

State the period of the sequence.

[1]
c.

Determine the exact value of ∑n=1101In\sum_{n=1}^{101} I_n∑n=1101​In​.

[3]

1.7.2 Types of sequence (A-level only) Questions

  1. A Level
  2. /Maths
  3. /1.7.2 Types of sequence (A-level only)