translation of 'reduction' in linear-algebra (#816)
translation of 'reduction' in linear-algebra (#816)

* translation of 'reduction' in linear-algebra

* Update linear-algebra.md

* Update linear-algebra.md

Co-authored-by: goldmermaid <fcb00cecbf879d17a80f4ce26a389eda39da7621@berkeley.edu>
d2l-ai/d2l-zh,mli/gluon-tutorials-zh,mli/gluon-tutorials-zh,mli/gluon-tutorials-zh,d2l-ai/d2l-zh,d2l-ai/d2l-zh,mli/gluon-tutorials-zh