Arithmetic series practice
For the arithmetic sequence \(6, 1, -4, \ldots\), find \(d\) and calculate \(S_{20}\).
AI writing feedback
How would you answer this question in your own words? The AI will analyse your response and give feedback on reasoning, evidence, and expression.
Worked practice: sequences and series
Find the common change or ratio, then use it to calculate the requested term or sum.