Q. Find the 6th term of the arithmetic sequence 3x−9,x−15,−x−21,…Answer:
Find Common Difference: To find the 6th term of the arithmetic sequence, we first need to determine the common difference (d) of the sequence. We can do this by subtracting the first term from the second term.Common difference (d) = (x−15) - (3x−9)
Calculate Common Difference: Now, let's perform the subtraction to find the common difference. d=x−15−3x+9d=−2x−6
Use Formula for nth Term: Next, we use the common difference to find the nth term of an arithmetic sequence using the formula:nth term = first term + (n−1)×common differenceWe want to find the 6th term, so n=6.6th term = (3x−9)+(6−1)×(−2x−6)
Simplify Expression: Now we simplify the expression to find the 6th term.6^{\text{th}}\) term = 3x - 9 + 5 \times (-2x - 6)6^{\text{th}}\) term = 3x - 9 - 10x - 30
Combine Like Terms: Combine like terms to get the final expression for the 6th term. 6th term = −7x−39
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