# How to find d in the RSA algorithm?

Given N and e, and knowing that N^0.25 <d< N^0.5, how is it possible to find d, and with what time complexity?

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• Our policy asks that on homework it's given evidence of having tried to solve the question. So please, add what you have concluded so far. Preliminary hint: what is the likelihood that there are several valid $d$ in the stated interval? Hint: consider the implications of Boneh and Durfee's Cryptanalysis of RSA with Private Key $d$ Less than $N^{0.292}$.
– fgrieu
2 days ago