一、从一道习题中发现了问题在杂志上读到一篇文章,内容是有关一道习题的思考:用一块长10厘米、宽6厘米的铁皮可以焊成一个无盖的长方体,这个长方体的体积最大是多少?根据教师的预设,学生逐步探索出三种方法,并画出相应的切割图。学生感觉到“同一块铁皮,切割方法不同,体积越来越大。”(1)a=6cm b=6cm h=1cm V=36cm~3(2)a=8.5cm b=3cm h=1.5cm V=38.25cm~3(3)a=5cm b=3.5cm h=2.5cm V=43.75cm~3最后,教师用肯定的语气总结:43.75cm~3是能切 First, found a problem from a problem Read an article in the magazine, the content is about a problem of thinking: with a 10 cm long, 6 cm wide metal can be welded into a coverless cuboid, the cuboid volume What is the maximum? According to the teacher’s default, students gradually explore the three methods, and draw the corresponding cut charts. The students felt that “the same piece of metal, cutting method is different, the volume is getting bigger.” (1) a = 6cm b = 6cm h = 1cm V = 36cm ~ 3 a = 8.5cm b = 3cm h = 1.5cm V = 38.25cm ~ 3 (3) a = 5cm b = 3.5cm h = 2.5cm V = 43.75cm ~ 3 Finally, the teacher concluded with a positive tone: 43.75cm ~ 3 is able to cut