What is the cost of computation of FFT? (Note: ‘N’ is the number of grid points).

What is the cost of computation of FFT? (Note: ‘N’ is the number of grid points). Correct Answer N log ⁡N

The cost of computation is reduced by FFT. FFT has a cost of computation of N log⁡ N orders. This is much lower than N2, especially when N is large. This reduces the problem of computation cost in the Spectral method.
Bissoy MCQ

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