QUESTION 1 1.1. The sequence 4; a; b;18 is such that 4; a and b form an arithmetic sequence and a;b and 18 form a geometric sequence.
1.1.1. Using the common difference of the arithmetic sequence, determine b in terms of a. (2)
1.1.2. Using the common ratio of the geometric sequence, determine b in terms of a. (2)
1.1.3. Hence or otherwise, calculate the value(s) of a and b. (8)
1.2. The sequence 4;9;x;37;.... is quadratic. 1.2.1. Calculate x. (4)
1.2.2. Hence, or otherwise, determine the nth term of the sequence. (5)


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