here , i am not understanding, how the sin, cos came ?? and how the G(2) gates are arranged like this ??? when we take candidate ground state as (alpha|11000> + beta|001100> + gamma|000011>)
Hi @Md_Zubair , welcome to the Forum!
This demo on Givens rotations has the answer 
You’ll see in this demo that the matrix for the two-qubit gate G contains sines and cosines.
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