填空题向量a，b互相垂直，且∣a∣＝1，则a·（a＋b）＝____．
填空题
向量a，b互相垂直，且∣a∣＝1，则a·（a＋b）＝____．
参考解析
解析：
由a⊥b，得a·b＝0而a2＝∣a∣2＝1．所以a·（a＋b）＝a2＋a·b＝1．
由a⊥b，得a·b＝0而a2＝∣a∣2＝1．所以a·（a＋b）＝a2＋a·b＝1．
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