【正文】 ...............................18 (一 ) 什么是質(zhì)量 ....................................................................................................................................18 (二 ) 常用單位 ........................................................................................................................................18 (三 ) 常用換算 ........................................................................................................................................18 五、 時(shí)間 ................................................................................................................................................18 (一 ) 什么是時(shí)間 ....................................................................................................................................18 (二 ) 常用單位 ........................................................................................................................................18 (三 ) 單位換算 ........................................................................................................................................18 六、 貨幣 ................................................................................................................................................19 (一 ) 什么是貨幣 ....................................................................................................................................19 (二 ) 常用單位 ........................................................................................................................................19 (三 ) 單位換算 ........................................................................................................................................19 第三章 代數(shù)初步知識(shí) ....................................................................................................................................19 一、 用字母表示數(shù) ................................................................................................................................19 (一 ) 用字母表示數(shù)的意義和作用 ........................................................................................................19 (二 ) 用字母表示常見的數(shù)量關(guān)系、運(yùn)算定律和性質(zhì)、幾何形體的計(jì)算公式 ................................19 (三 ) 用字母表示數(shù)的寫法 ....................................................................................................................21 (四 ) 將數(shù)值代入式子求值 ....................................................................................................................21 二、 簡易方程 ........................................................................................................................................21 方程和方程的解 ......................................................................................................................................21 三、 解方程 ............................................................................................................................................22 四、 列方程解應(yīng)用題 ............................................................................................................................22 (一 ) 列方程解應(yīng)用題的意義 ................................................................................................................22 (二 ) 列方程解答應(yīng)用題的步驟 ............................................................................................................22 (三 ) 列方程解應(yīng)用題的方法 ................................................................................................................22 (四 ) 列方程解應(yīng)用題的范圍 ................................................................................................................22 五、 比和比例 ........................................................................................................................................23 (一 ) 比的意義和性質(zhì) ............................................................................................................................23 (二 ) 比例的意義和性質(zhì) ........................................................................................................................23 專注于中小學(xué)教育 聯(lián)系電話： 18991890913 4 (三 ) 正比例和反比例 ............................................................................................................................24 第四章 幾何的初步知識(shí) ................................................................................................................................24 一、 線和角 ............................................................................................................................................24 (一 ) 線 ....................................................................................................................................................24 (二 ) 角 ....................................................................................................................................................25 二、 平面圖形 ........................................................................................................................................25 (一 ) 長方形 ............................................................................................................................................25 (二 ) 正方形 ............................................................................................................................................25 (三 ) 三角形 ............................................................................................................................................25 (四 ) 平行四邊形 ....................................................................................................................................26 (五 ) 梯形 ................................................................................................................................................26 (六 ) 圓 ....................................................................................................................................................27 (七 ) 扇形 ...................................................