Cho hai số phức <span class="MathJax_Preview" style="color: inherit;"><span class="MJXp-math" id="MJXp-Span-1"><span class="MJXp-mstyle" id="MJXp-Span-2"><span class="MJXp-mi MJXp-italic" id="MJXp-Span-3">z</span><span class="MJXp-mo" id="MJXp-Span-4" style="margin-left: 0.333em; margin-right: 0.333em;">=</span><span class="MJXp-mn" id="MJXp-Span-5">6</span><span class="MJXp-mo" id="MJXp-Span-6" style="margin-left: 0.267em; margin-right: 0.267em;">+</span><span class="MJXp-mn" id="MJXp-Span-7">5</span><span class="MJXp-mi MJXp-italic" id="MJXp-Span-8">i</span><span class="MJXp-mo" id="MJXp-Span-9" style="margin-left: 0em; margin-right: 0.222em;">,</span><span class="MJXp-mspace" id="MJXp-Span-10" style="width: 0.167em; height: 0em;"></span></span></span></span><span id="MathJax-Element-1-Frame" class="mjx-chtml MathJax_CHTML MJXc-processed" tabindex="0" style="font-size: 127%;"><span id="MJXc-Node-1" class="mjx-math"><span id="MJXc-Node-2" class="mjx-mrow"><span id="MJXc-Node-3" class="mjx-mstyle"><span id="MJXc-Node-4" class="mjx-mrow" style="font-size: 144%;"><span id="MJXc-Node-5" class="mjx-mi"><span class="mjx-char MJXc-TeX-math-I" style="padding-top: 0.199em; padding-bottom: 0.298em; padding-right: 0.003em;">z</span></span><span id="MJXc-Node-6" class="mjx-mo MJXc-space3"><span class="mjx-char MJXc-TeX-main-R" style="padding-top: 0.101em; padding-bottom: 0.298em;">=</span></span><span id="MJXc-Node-7" class="mjx-mn MJXc-space3"><span class="mjx-char MJXc-TeX-main-R" style="padding-top: 0.396em; padding-bottom: 0.347em;">6</span></span><span id="MJXc-Node-8" class="mjx-mo MJXc-space2"><span class="mjx-char MJXc-TeX-main-R" style="padding-top: 0.298em; padding-bottom: 0.445em;">+</span></span><span id="MJXc-Node-9" class="mjx-mn MJXc-space2"><span class="mjx-char MJXc-TeX-main-R" style="padding-top: 0.396em; padding-bottom: 0.347em;">5</span></span><span id="MJXc-Node-10" class="mjx-mi"><span class="mjx-char MJXc-TeX-math-I" style="padding-top: 0.445em; padding-bottom: 0.298em;">i</span></span><span id="MJXc-Node-11" class="mjx-mo"><span class="mjx-char MJXc-TeX-main-R" style="margin-top: -0.145em; padding-bottom: 0.544em;">,</span></span><span id="MJXc-Node-12" class="mjx-mspace" style="font-size: 69.4%; width: 0.167em; height: 0px;"></span></span></span></span></span></span><script type="math/tex" id="MathJax-Element-1">\Large z=6+5i,\,</script><span class="MathJax_Preview" style="color: inherit;"><span class="MJXp-math" id="MJXp-Span-11"><span class="MJXp-mstyle" id="MJXp-Span-12"><span class="MJXp-msup" id="MJXp-Span-13"><span class="MJXp-mrow" id="MJXp-Span-14" style="margin-right: 0.05em;"><span class="MJXp-mi MJXp-italic" id="MJXp-Span-15">z</span></span><span class="MJXp-mo MJXp-script" id="MJXp-Span-16" style="vertical-align: 0.5em;">′</span></span><span class="MJXp-mo" id="MJXp-Span-17" style="margin-left: 0.333em; margin-right: 0.333em;">=</span><span class="MJXp-mn" id="MJXp-Span-18">5</span><span class="MJXp-mo" id="MJXp-Span-19" style="margin-left: 0.267em; margin-right: 0.267em;">−</span><span class="MJXp-mn" id="MJXp-Span-20">4</span><span class="MJXp-mi MJXp-italic" id="MJXp-Span-21">i</span><span class="MJXp-mo" id="MJXp-Span-22" style="margin-left: 0.267em; margin-right: 0.267em;">+</span><span class="MJXp-mi MJXp-italic" id="MJXp-Span-23">z</span></span></span></span><span id="MathJax-Element-2-Frame" class="mjx-chtml MathJax_CHTML MJXc-processing" tabindex="0" style="font-size: 127%;"></span><script type="math/tex" id="MathJax-Element-2">\Large {z}'=5-4i+z</script>. Tìm mođun của

Cho hai số phức z=6+5i,z=54i+z. Tìm mođun của

4/5

Tác giả: Thầy Tùng

Đăng ngày: 18 Aug 2022

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Câu hỏi:

Cho hai số phức z=6+5i,z=54i+z. Tìm mođun của số phức w=z.z

Đáp án án đúng là: C

Lời giải chi tiết:

z=6+5i z=54i+6+5i=11+i.

w=z.z=(6+5i)(11+i)=61+61i

|w|=612.