KwickClips Java · 41 sec · free
What is the Big O of 3n² + 5n + 9?
Short answer. O(n²).
Do you keep the constant 3 in 3n?
No. Constants are dropped, so it is O(n).
Keep the dominant term
| Steps | Big O |
|---|---|
| 3n + 5 | O(n) |
| 3n² + 5n + 9 | O(n²) |
| 50 | O(1) |
Remember
| Keep the fastest term |
| Drop constants |
Three n squared plus five n plus nine. What is its Big O? Keep the fastest growing term. Three n plus five is order n. With n squared, it is order n squared. A fixed fifty is order one. Keep the fastest term. Drop the constants.
This clip is from the full lesson: Algorithm Complexity and Big O Notation — 7 minutes, with the tables, the quick answers and the whole lesson in text.
Useful for: ISC Class 12 Computer Science (868), ISC Class 12 Computer Science (868), ISC Class 12 Computer Science (868), ISC Class 12 Computer Science (868)
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