Bài 2: Các phép toán với đa thức nhiều biến
Thực hành 5 trang 16 Toán 8 tập 1
<p><strong>Thực h&agrave;nh 5 trang 16 To&aacute;n 8 Tập 1:&nbsp;</strong>Thực hiện c&aacute;c ph&eacute;p chia:</p> <div class="ads_ads ads_1"><ins class="adsbygoogle" data-ad-client="ca-pub-2373417360267295" data-ad-slot="9405778504" data-ad-format="auto" data-full-width-responsive="true" data-adsbygoogle-status="done" data-ad-status="unfilled"> <div id="aswift_1_host" tabindex="0" title="Advertisement" aria-label="Advertisement"></div> </ins></div> <p>a) (5ab &ndash; 2a<sup>2</sup>) : a;</p> <p>b) (6x<sup>2</sup>y<sup>2</sup>&nbsp;&ndash; xy<sup>2</sup>&nbsp;+ 3x<sup>2</sup>y) : (&ndash;3xy).</p> <p><strong>Lời giải:</strong></p> <p>a) (5ab &ndash; 2a<sup>2</sup>) : a</p> <p>= (5ab : a) + (&ndash;2a<sup>2</sup>&nbsp;: a)</p> <p>= 5.(a : a).b + [&ndash; 2.(a<sup>2</sup>&nbsp;: a)]</p> <p>= 5b &ndash; 2a.</p> <p>b) (6x<sup>2</sup>y<sup>2</sup>&nbsp;&ndash; xy<sup>2</sup>&nbsp;+ 3x<sup>2</sup>y) : (&ndash;3xy)</p> <p>= [6x<sup>2</sup>y<sup>2</sup>&nbsp;: (&ndash;3xy)] + [&ndash; xy<sup>2</sup>&nbsp;: (&ndash;3xy)] + [3x<sup>2</sup>y : (&ndash;3xy)]</p> <p>= [6 : (&ndash;3)].(x<sup>2</sup>&nbsp;: x).(y<sup>2</sup>&nbsp;: y) + [(&ndash;1) : (&ndash;3)].(x : x).(y<sup>2</sup>&nbsp;: y) + [3 : (&ndash;3)].(x<sup>2</sup>&nbsp;: x).(y : y)</p> <p>= &ndash;2xy +&nbsp;<span id="MathJax-Element-1-Frame" class="mjx-chtml MathJax_CHTML" style="box-sizing: border-box; display: inline-block; line-height: 0; text-indent: 0px; text-align: left; text-transform: none; font-style: normal; font-weight: normal; font-size: 21.78px; letter-spacing: normal; overflow-wrap: normal; word-spacing: normal; white-space: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; margin: 0px; padding: 1px 0px; position: relative;" tabindex="0" role="presentation" data-mathml="&lt;math xmlns=&quot;http://www.w3.org/1998/Math/MathML&quot;&gt;&lt;mfrac&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;mn&gt;3&lt;/mn&gt;&lt;/mfrac&gt;&lt;/math&gt;"><span id="MJXc-Node-1" class="mjx-math" aria-hidden="true"><span id="MJXc-Node-2" class="mjx-mrow"><span id="MJXc-Node-3" class="mjx-mfrac"><span class="mjx-box MJXc-stacked"><span class="mjx-numerator"><span id="MJXc-Node-4" class="mjx-mn"><span class="mjx-char MJXc-TeX-main-R">1</span></span></span><span class="mjx-denominator"><span id="MJXc-Node-5" class="mjx-mn"><span class="mjx-char MJXc-TeX-main-R">3</span></span></span></span></span></span></span><span class="MJX_Assistive_MathML" role="presentation"><math xmlns="http://www.w3.org/1998/Math/MathML"><mfrac><mn>1</mn><mn>3</mn></mfrac></math></span></span>y &ndash; x.</p>
Xem lời giải bài tập khác cùng bài