9231 FP1 · Notes & worked examples
Check a final answer, then explain the reasoning on paper. Guest progress stays in this browser; an account saves future checks without overwriting your first result.
Recall
Maths4U Original · Short practice
Define \(S_n=\sum_{r=1}^n(14r+13)\) for positive integers n.
Find the sum from \(\displaystyle r=1\) to \(\displaystyle r=15\) of 14r+13.
Enter one number or fraction. Use at least six decimal places when needed; a distribution calculator may be used for probabilities.
Fresh review variant
Maths4U Original · Short practice
Define \(S_n=\sum_{r=1}^n(15r+14)\) for positive integers n.
Find the sum from \(\displaystyle r=1\) to \(\displaystyle r=16\) of 15r+14.
Enter one number or fraction. Use at least six decimal places when needed; a distribution calculator may be used for probabilities.
Method
Maths4U Original · Short practice
Define \(S_n=\sum_{r=1}^n(15r+14)\) for positive integers n.
Find the term added when extending \(\displaystyle S_{16}\) to \(\displaystyle S_{17}\).
Enter one number or fraction. Use at least six decimal places when needed; a distribution calculator may be used for probabilities.
Fresh review variant
Maths4U Original · Short practice
Define \(S_n=\sum_{r=1}^n(16r+15)\) for positive integers n.
Find the term added when extending \(\displaystyle S_{17}\) to \(\displaystyle S_{18}\).
Enter one number or fraction. Use at least six decimal places when needed; a distribution calculator may be used for probabilities.
Apply
Maths4U Original · Short practice
\(u_1=15,\ u_{n+1}=4u_n+16\) for \(\displaystyle n\ge 1\).
Find \(\displaystyle u_{7}\).
Enter one number or fraction. Use at least six decimal places when needed; a distribution calculator may be used for probabilities.
Fresh review variant
Maths4U Original · Short practice
\(u_1=16,\ u_{n+1}=2u_n+17\) for \(\displaystyle n\ge 1\).
Find \(\displaystyle u_{5}\).
Enter one number or fraction. Use at least six decimal places when needed; a distribution calculator may be used for probabilities.
Check understanding
Maths4U Original · Short practice
\(u_1=16,\ u_{n+1}=2u_n+17\) for \(\displaystyle n\ge 1\).
Find \(\displaystyle u_{5}-u_{4}\).
Enter one number or fraction. Use at least six decimal places when needed; a distribution calculator may be used for probabilities.
Fresh review variant
Maths4U Original · Short practice
\(u_1=17,\ u_{n+1}=3u_n+18\) for \(\displaystyle n\ge 1\).
Find \(\displaystyle u_{6}-u_{5}\).
Enter one number or fraction. Use at least six decimal places when needed; a distribution calculator may be used for probabilities.