meili 发表于 2022-10-27 15:36:14

若复数z=a+3i1−2i(a∈R,i是虚数单位),且z是纯虚数,则|a+2i|等于______.

<p>问题:若复数z=a+3i1−2i(a∈R,i是虚数单位),且z是纯虚数,则|a+2i|等于______.
<p>答案:↓↓↓<p class="nav-title mt10" style="border-top:1px solid #ccc;padding-top: 10px;">汪传旭的回答:<div class="content-b">网友采纳  z=a+3i1−2i=(a+3i)(1+2i)(1−2i)(1+2i)=a−6+(2a+3)i5
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