Bài tập cuối chương 2
Hướng dẫn Giải Bài 2 (Trang 45, SGK Toán 7, Tập 1, Bộ Chân Trời Sáng Tạo)
<p><strong>B&agrave;i 2 (Trang 45, SGK To&aacute;n 7, Tập 1, Bộ Ch&acirc;n Trời S&aacute;ng Tạo)</strong></p> <p>Hai số 3,4(24) v&agrave; 3,(42) c&oacute; bằng nhau kh&ocirc;ng?</p> <p><strong><span style="text-decoration: underline;"><em>Hướng dẫn giải:</em></span></strong></p> <p>Ta c&oacute;:&nbsp;</p> <p><math xmlns="http://www.w3.org/1998/Math/MathML"><mn>3</mn><mo>,</mo><mn>4</mn><mo>(</mo><mn>24</mn><mo>)</mo><mo>&#160;</mo><mo>=</mo><mo>&#160;</mo><mn>3</mn><mo>,</mo><mn>42422</mn><mo>&#160;</mo><mo>=</mo><mo>&#160;</mo><mn>3</mn><mo>,</mo><mn>4</mn><mo>&#160;</mo><mo>+</mo><mo>&#160;</mo><mn>0</mn><mo>,</mo><mn>02424</mn><mspace linebreak="newline"/><mo>=</mo><mo>&#160;</mo><mn>3</mn><mo>,</mo><mn>4</mn><mo>&#160;</mo><mo>+</mo><mo>&#160;</mo><mfrac><mn>1</mn><mn>10</mn></mfrac><mo>.</mo><mn>24</mn><mo>.</mo><mfrac><mn>1</mn><mn>99</mn></mfrac><mspace linebreak="newline"/><mo>=</mo><mfrac><mn>17</mn><mn>5</mn></mfrac><mo>&#160;</mo><mo>+</mo><mo>&#160;</mo><mfrac><mn>4</mn><mn>165</mn></mfrac><mo>&#160;</mo><mo>=</mo><mo>&#160;</mo><mfrac><mn>561</mn><mn>165</mn></mfrac><mo>&#160;</mo><mo>+</mo><mo>&#160;</mo><mfrac><mn>4</mn><mn>165</mn></mfrac><mspace linebreak="newline"/><mo>=</mo><mo>&#160;</mo><mfrac><mn>565</mn><mn>165</mn></mfrac><mo>&#160;</mo><mo>=</mo><mo>&#160;</mo><mfrac><mn>113</mn><mn>33</mn></mfrac><mspace linebreak="newline"/><mn>3</mn><mo>,</mo><mo>(</mo><mn>42</mn><mo>)</mo><mo>&#160;</mo><mo>=</mo><mo>&#160;</mo><mn>3</mn><mo>,</mo><mn>4242</mn><mo>.</mo><mo>.</mo><mo>.</mo><mo>=</mo><mo>&#160;</mo><mn>3</mn><mo>&#160;</mo><mo>+</mo><mo>&#160;</mo><mn>0</mn><mo>,</mo><mn>4242</mn><mo>.</mo><mo>.</mo><mo>.</mo><mspace linebreak="newline"/><mo>=</mo><mn>3</mn><mo>&#160;</mo><mo>+</mo><mo>&#160;</mo><mn>42</mn><mo>.</mo><mfrac><mn>1</mn><mn>99</mn></mfrac><mo>&#160;</mo><mo>=</mo><mo>&#160;</mo><mn>3</mn><mo>&#160;</mo><mo>+</mo><mo>&#160;</mo><mfrac><mn>14</mn><mn>33</mn></mfrac><mspace linebreak="newline"/><mo>=</mo><mo>&#160;</mo><mfrac><mn>99</mn><mn>33</mn></mfrac><mo>&#160;</mo><mo>+</mo><mo>&#160;</mo><mfrac><mn>14</mn><mn>33</mn></mfrac><mo>&#160;</mo><mo>=</mo><mo>&#160;</mo><mfrac><mn>113</mn><mn>33</mn></mfrac></math>&nbsp;</p> <p>Vậy hai số 3,4(24) = 3,(42) do c&ugrave;ng bằng ph&acirc;n số&nbsp;<math xmlns="http://www.w3.org/1998/Math/MathML"><mfrac><mn>113</mn><mn>33</mn></mfrac><mo>.</mo></math></p>
Xem lời giải bài tập khác cùng bài