An industrial kiln's control system modulates the internal temperature, TnT_nTn in degrees Celsius, at discrete time steps nnn. The temperature sequence T1,T2,T3,…T_1, T_2, T_3, \dotsT1,T2,T3,… is defined by Tn+1=1800−TnT_{n+1} = 1800 - T_nTn+1=1800−Tn where T1=850T_1 = 850T1=850 is the initial temperature reading.
Find the value of
(i) T2T_2T2
(ii) T121T_{121}T121
∑n=140(0.1Tn+5)\sum_{n=1}^{40} (0.1T_n + 5)∑n=140(0.1Tn+5)
Practise Edexcel A Level Maths Sequences and Series with exam-style questions for A Level Maths. 100 questions covering 3.1 Arithmetic Sequences, 3.2 Arithmetic Series, 3.3 Geometric Sequences, 3.4 Geometric Series, 3.5 Sum to Infinity, 3.6 Sigma Notation, 3.7 Recurrence Relations, and 3.8 Modelling with Series, matched to the Edexcel A Level Maths (9MA0) specification and written in Paper 1, Paper 2 and Paper 3 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.