The directsumdecomposition of the addition of a linear transformation under the coprime polynomial was given, and it was used in the proof of some equality about the rank of idempotent matrix.
给出了两两互素多项式下线性变换的核的直和分解，并应用于幂等矩阵（对合矩阵）的秩的等式证明中。
2
In this paper, we have discussed root subspace decomposition of linear space, and for the linear space have decomposed directsum of root subspace, a primary proof is given.