Bài 2: Đồ thị của hàm số <math xmlns="http://www.w3.org/1998/Math/MathML"><mi>y</mi><mo>=</mo><mi>a</mi><msup><mi>x</mi><mn>2</mn></msup><mo>&#160;</mo><mfenced><mrow><mi>a</mi><mo>&#8800;</mo><mn>0</mn></mrow></mfenced></math>
Hướng dẫn giải Bài 4 (Trang 36 SGK Toán Đại số 9, Tập 2)
<p>Cho hai h&agrave;m số: y=<math xmlns="http://www.w3.org/1998/Math/MathML"><mfrac><mn>3</mn><mn>2</mn></mfrac></math>x<sup>2</sup>, y=<math xmlns="http://www.w3.org/1998/Math/MathML"><mfrac><mrow><mo>-</mo><mn>3</mn></mrow><mn>2</mn></mfrac></math>x<sup>2</sup>. Điền v&agrave;o chỗ trống của c&aacute;c bảng sau rồi vẽ hai đồ thị tr&ecirc;n c&ugrave;ng một mặt phẳng tọa độ.</p> <table style="border-collapse: collapse; width: 63.2933%; height: 64.3906px;" border="1"> <tbody> <tr style="height: 23.3906px;"> <td style="width: 16.3212%; height: 23.3906px; text-align: center;">x</td> <td style="width: 16.5803%; height: 23.3906px; text-align: center;">-2</td> <td style="width: 16.9689%; height: 23.3906px; text-align: center;">-1</td> <td style="width: 16.4508%; height: 23.3906px; text-align: center;">0</td> <td style="width: 16.5803%; height: 23.3906px; text-align: center;">1</td> <td style="width: 17.0984%; height: 23.3906px; text-align: center;">2</td> </tr> <tr style="height: 41px;"> <td style="width: 16.3212%; height: 41px; text-align: center;">y=<math xmlns="http://www.w3.org/1998/Math/MathML"><mfrac><mn>3</mn><mn>2</mn></mfrac></math>x<sup>2</sup></td> <td style="width: 16.5803%; height: 41px; text-align: center;">&nbsp;</td> <td style="width: 16.9689%; height: 41px; text-align: center;">&nbsp;</td> <td style="width: 16.4508%; height: 41px; text-align: center;">&nbsp;</td> <td style="width: 16.5803%; height: 41px; text-align: center;">&nbsp;</td> <td style="width: 17.0984%; height: 41px; text-align: center;">&nbsp;</td> </tr> </tbody> </table> <p>&nbsp;</p> <table style="border-collapse: collapse; width: 63.2075%;" border="1"> <tbody> <tr> <td style="width: 16.3735%; text-align: center;">x</td> <td style="width: 16.6441%; text-align: center;">-2</td> <td style="width: 16.6441%; text-align: center;">-1</td> <td style="width: 16.6441%; text-align: center;">0</td> <td style="width: 16.6441%; text-align: center;">1</td> <td style="width: 17.0501%; text-align: center;">2</td> </tr> <tr> <td style="width: 16.3735%; text-align: center;">y=<math xmlns="http://www.w3.org/1998/Math/MathML"><mfrac><mrow><mo>-</mo><mn>3</mn></mrow><mn>2</mn></mfrac></math>x<sup>2</sup></td> <td style="width: 16.6441%; text-align: center;">&nbsp;</td> <td style="width: 16.6441%; text-align: center;">&nbsp;</td> <td style="width: 16.6441%; text-align: center;">&nbsp;</td> <td style="width: 16.6441%; text-align: center;">&nbsp;</td> <td style="width: 17.0501%; text-align: center;">&nbsp;</td> </tr> </tbody> </table> <p>Nhận x&eacute;t về t&iacute;nh đối xứng của hai đồ thị đối với trục Ox.</p> <p><strong>Giải:</strong></p> <p>Thực hiện ph&eacute;p t&iacute;nh v&agrave; điền v&agrave;o chỗ trống ta được bảng sau:<span class="mce-nbsp-wrap" contenteditable="false">&nbsp;&nbsp;&nbsp;</span><span class="mce-nbsp-wrap" contenteditable="false">&nbsp;&nbsp;&nbsp;</span><span class="mce-nbsp-wrap" contenteditable="false">&nbsp;&nbsp;&nbsp;</span><span class="mce-nbsp-wrap" contenteditable="false">&nbsp;&nbsp;&nbsp;</span><span class="mce-nbsp-wrap" contenteditable="false">&nbsp;&nbsp;&nbsp;</span><span class="mce-nbsp-wrap" contenteditable="false">&nbsp;&nbsp;&nbsp;</span><span class="mce-nbsp-wrap" contenteditable="false">&nbsp;&nbsp;&nbsp;</span><span class="mce-nbsp-wrap" contenteditable="false">&nbsp;&nbsp;&nbsp;</span><span class="mce-nbsp-wrap" contenteditable="false">&nbsp;&nbsp;&nbsp;</span><span class="mce-nbsp-wrap" contenteditable="false">&nbsp;&nbsp;&nbsp;</span><span class="mce-nbsp-wrap" contenteditable="false">&nbsp;&nbsp;&nbsp;</span><span class="mce-nbsp-wrap" contenteditable="false">&nbsp;&nbsp;&nbsp;</span><span class="mce-nbsp-wrap" contenteditable="false">&nbsp;&nbsp;&nbsp;</span><span class="mce-nbsp-wrap" contenteditable="false">&nbsp;&nbsp;&nbsp;</span></p> <p><span class="mce-nbsp-wrap" contenteditable="false">&nbsp;&nbsp;&nbsp;</span><span class="mce-nbsp-wrap" contenteditable="false">&nbsp;&nbsp;&nbsp;</span><span class="mce-nbsp-wrap" contenteditable="false">&nbsp;&nbsp;&nbsp;</span><span class="mce-nbsp-wrap" contenteditable="false">&nbsp;&nbsp;&nbsp;</span><span class="mce-nbsp-wrap" contenteditable="false">&nbsp;&nbsp;&nbsp;</span><span class="mce-nbsp-wrap" contenteditable="false">&nbsp;&nbsp;&nbsp;</span><span class="mce-nbsp-wrap" contenteditable="false">&nbsp;&nbsp;&nbsp;</span><span class="mce-nbsp-wrap" contenteditable="false">&nbsp;&nbsp;&nbsp;</span><span class="mce-nbsp-wrap" contenteditable="false">&nbsp;&nbsp;&nbsp;</span><span class="mce-nbsp-wrap" contenteditable="false">&nbsp;&nbsp;&nbsp;</span><span class="mce-nbsp-wrap" contenteditable="false">&nbsp;&nbsp;&nbsp;</span><span class="mce-nbsp-wrap" contenteditable="false">&nbsp;&nbsp;&nbsp;</span><span class="mce-nbsp-wrap" contenteditable="false">&nbsp;&nbsp;&nbsp;</span>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;</p> <table style="border-collapse: collapse; width: 64.4909%;" border="1"> <tbody> <tr> <td style="width: 16.6376%; text-align: center;">x</td> <td style="width: 16.6376%; text-align: center;">-2</td> <td style="width: 16.6376%; text-align: center;">-1</td> <td style="width: 16.7247%; text-align: center;">0</td> <td style="width: 16.6376%; text-align: center;">1</td> <td style="width: 16.7247%; text-align: center;">2</td> </tr> <tr> <td style="width: 16.6376%; text-align: center;">y=<math xmlns="http://www.w3.org/1998/Math/MathML"><mfrac><mn>3</mn><mn>2</mn></mfrac></math>x<sup>2</sup></td> <td style="width: 16.6376%; text-align: center;">6</td> <td style="width: 16.6376%; text-align: center;"><math xmlns="http://www.w3.org/1998/Math/MathML"><mfrac><mn>3</mn><mn>2</mn></mfrac></math></td> <td style="width: 16.7247%; text-align: center;">0</td> <td style="width: 16.6376%; text-align: center;"><math xmlns="http://www.w3.org/1998/Math/MathML"><mfrac><mn>3</mn><mn>2</mn></mfrac></math></td> <td style="width: 16.7247%; text-align: center;">6</td> </tr> </tbody> </table> <p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;</p> <table style="border-collapse: collapse; width: 64.3168%;" border="1"> <tbody> <tr> <td style="width: 16.5545%; text-align: center;">x</td> <td style="width: 16.6891%; text-align: center;">-2</td> <td style="width: 16.5545%; text-align: center;">-1</td> <td style="width: 16.8237%; text-align: center;">0</td> <td style="width: 16.5545%; text-align: center;">1</td> <td style="width: 16.8237%; text-align: center;">2</td> </tr> <tr> <td style="width: 16.5545%; text-align: center;">y=<math xmlns="http://www.w3.org/1998/Math/MathML"><mfrac><mrow><mo>-</mo><mn>3</mn></mrow><mn>2</mn></mfrac></math>x<sup>2</sup></td> <td style="width: 16.6891%; text-align: center;">-6</td> <td style="width: 16.5545%; text-align: center;"><math xmlns="http://www.w3.org/1998/Math/MathML"><mfrac><mrow><mo>-</mo><mn>3</mn></mrow><mn>2</mn></mfrac></math></td> <td style="width: 16.8237%; text-align: center;">0</td> <td style="width: 16.5545%; text-align: center;"><math xmlns="http://www.w3.org/1998/Math/MathML"><mfrac><mrow><mo>-</mo><mn>3</mn></mrow><mn>2</mn></mfrac></math></td> <td style="width: 16.8237%; text-align: center;">-6</td> </tr> </tbody> </table> <p>Vẽ đồ thị: h&igrave;nh b&ecirc;n&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&nbsp;</p> <p>Nhận x&eacute;t: Đồ thị của h&agrave;m số đối xứng với nhau qua trục Ox.&nbsp; &nbsp; &nbsp;&nbsp;</p> <p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;<img class="wscnph" src="https://static.colearn.vn:8413/v1.0/upload/library/16022022/80998ba0-215a-4142-865b-c10c7f1a3c19.PNG" /></p> <p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&nbsp;</p> <p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;</p>
Hướng dẫn Giải Bài 4 (Trang 36, SGK Toán 9, Tập 2)
GV: GV colearn
Xem lời giải bài tập khác cùng bài
Video hướng dẫn giải bài tập
Hướng dẫn Giải Bài 4 (Trang 36, SGK Toán 9, Tập 2)
GV: GV colearn