Having perused the stackexchange, I discovered some related questions, however am having problem understanding arrive on the answer to (n-1)*x=1 mod np, the place:

n: Finite group order of the Bitcoin secp256k1 curve

n=115792089237316195423570985008687907852837564279074904382605163141518161494337

p: Prime order of the curve

p=115792089237316195423570985008687907853269984665640564039457584007908834671663

np: (n-1)+(p-1)

np=231584178474632390847141970017375815706107548944715468422062747149426996165998

and (n-1) shouldn’t be coprime to modulo np.

Having carried out the next step of np/2 and including .5 to consequence one, in order to attain:

F1=115792089237316195423570985008687907853053774472357734211031373574713498083000

Then subtracting the preliminary consequence with .5 to attain:

F2=115792089237316195423570985008687907853053774472357734211031373574713498082999

And following directions from solutions to associated posts, (n-1) is to be multiplicativeley inversed over mod F1 and F2. Nevertheless, neither F1 or F2 are coprime to (n-1). With a view to overcome this, it’s defined that GCD and CRT are for use with the intention to precisely calculate the modular inverse.

What steps are required and the way are the operations carried out to perform this?

Thanks.