喺抽象代數入面,直和(英文:direct sum)係一種構作新「物件」嘅方法。喺好多嘅範疇入面都可以做直和,例如阿標羣、羣、向量空間、模等等。爲咗舉例,假設A同B羣,咁A同B嘅直和就係所有(a,b)咁嘅樣嘅元素,當中,而羣結構就係由公式去定義。換言之,佢嘅加法係逐個逐個位去做嘅。
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