Skip to content

Course home

Sign up

1.6 Sequences and Series

EasyMediumHard
1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950
Question 17

The temperature of a specialized metal alloy at the end of stage nnn of a cooling process is denoted by TnT_nTn​, measured in Kelvin. The process is modeled by the recurrence relation

Tn+1=ωTn+84 T_{n+1} = \omega T_n + 84 Tn+1​=ωTn​+84

where T1=1200T_1 = 1200T1​=1200 and ω\omegaω is a constant.

a.

Find an expression, in terms of ω\omegaω, for T2T_2T2​.

[1]
bi.

It is given that the temperature at the end of the third stage is T3=822T_3 = 822T3​=822.

Show that ω\omegaω satisfies the equation

200ω2+14ω−123=0 200\omega^2 + 14\omega - 123 = 0 200ω2+14ω−123=0
[3]
bii.

It is given that the sequence of temperatures is a decreasing sequence. Find the value of T4T_4T4​ and the value of T5T_5T5​.

[4]
ci.

The limit of TnT_nTn​ as n→∞n \to \inftyn→∞ is LLL.

Write down an equation for LLL.

[1]
cii.

Find the value of LLL.

[1]
Markscheme

1.6 Sequences and Series Questions

  1. A Level
  2. /Maths
  3. /1.6 Sequences and Series

308 exam-style questions on OCR (MEI) A Level Maths 1.6 Sequences and Series, covering 1.6.1 Binomial expansion for positive integer n, 1.6.2 Factorial and combinations notation, 1.6.3 Binomial expansion for rational n (A-level only), 1.6.4 Binomial expansion of (a + bx)^n via factoring (A-level only), 1.6.5 Binomial approximating polynomials (A-level only), 1.6.6 What a sequence is; finite and infinite (A-level only), 1.6.7 Generate a sequence by formula or recurrence (A-level only), 1.6.8 A series as a sum of terms (A-level only), 1.6.9 Sigma notation (A-level only), 1.6.10 Increasing, decreasing and periodic sequences (A-level only), 1.6.11 Convergent and divergent sequences (A-level only), 1.6.12 Arithmetic sequences and series (A-level only), 1.6.13 Standard formulae for arithmetic series (A-level only), 1.6.14 Geometric sequences and series (A-level only), 1.6.15 Standard formulae for geometric series (A-level only), 1.6.16 Sum to infinity of a geometric series (A-level only), and 1.6.17 Sequences and series in modelling (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.

Question bank