Q. Find an explicit formula for the arithmetic sequence−2,−14,−26,−38,….. Note: the first term should be d(1).d(n)=
Identify the sequence type and pattern: Identify the type of sequence and the pattern. The sequence -2 ext{,} -14 ext{,} -26 ext{,} -38 ext{,} \ ext{...} ext{)} decreases by the same amount each time, which indicates it is an arithmetic sequence. The common difference \$d can be found by subtracting any term from the term that follows it.Calculation: d=−14−(−2)=−14+2=−12
Calculate the common difference: Use the explicit formula for an arithmetic sequence, which is d(n)=d(1)+(n−1)d, where d(1) is the first term and d is the common difference.In this sequence, the first term d(1) is −2 and the common difference d is −12.
Use the explicit formula for arithmetic sequence: Substitute the values of d(1) and d into the formula to find the explicit formula for the sequence.Calculation: d(n)=−2+(n−1)(−12)
Substitute values into the formula: Simplify the expression to get the final explicit formula for the sequence.Calculation: d(n)=−2−12(n−1)=−2−12n+12=−12n+10
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