Practice question · Select all that apply
Select every statement about solving Ax = b numerically that is TRUE.
Hints
- Two options claim more than the lesson allows, one about iteration, one about conditioning.
- Iterative methods refine an approximation; where does that process end?
Show the answer
- A. Doubling n multiplies the direct method's work by about 8
- B. Pivoting avoids dividing by a zero or tiny pivot
- D. A large condition number means the solution is very sensitive to input error
Why
Cubic cost, the purpose of pivoting and the meaning of the condition number are all exactly as taught. Iterative methods approach the answer rather than terminating at it, and conditioning is a defect of the problem that no algorithm can undo.
Practise Solving Linear Systems Numerically
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