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1、对于闪光灯，很多人是恐惧的。同时驾驭两三灯，甚至五灯，的确是很难。但是如果仅仅只是一灯的话，问题就简单很多。更何况即便是，一人一灯Changing the inequality into equality under what condition is the current research key point. This paper uses the and its elementary operation corresponds the partitioned matrix, prove that when satisfy the certain condition, we have.3
2、.3 平方差公式与 平方差公式与 完全平方公式完全平方公式( (二二) )对于闪光灯，很多人是恐惧的。同时驾驭两三灯，甚至五灯，的确是很难。但是如果仅仅只是一灯的话，问题就简单很多。更何况即便是，一人一灯Changing the inequality into equality under what condition is the current research key point. This paper uses the and its elementary operation corresponds the partitioned matrix, prove that when sat
3、isfy the certain condition, we have 完 全 平 方 公 式一块边长为a米的正方形实验田，做一做做一做图图1 1 6 6a a因需要将因需要将 其边长增加其边长增加 b b 米。米。形成四块形成四块 实验田，以种植不同的新品种实验田，以种植不同的新品种 ( (如图如图1 1 6 6). ).你能用不同的形式表示实你能用不同的形式表示实 验田的总面积验田的总面积, , 并进行比较并进行比较. . a ab bb b法一法一 直直 接接 求求总面积总面积=( (a a+b b) ) ；2 2法二法二间间 接接 求求总面积总面积=a a2 2+a ab b+a ab
4、 b+b b2 2. .( (a a+b b) )2 2=a a2 2+a ab b+ b b2 2. .你发现了什么你发现了什么? ? 探索探索: : 2 2公式公式: :对于闪光灯，很多人是恐惧的。同时驾驭两三灯，甚至五灯，的确是很难。但是如果仅仅只是一灯的话，问题就简单很多。更何况即便是，一人一灯Changing the inequality into equality under what condition is the current research key point. This paper uses the and its elementary operation corre
5、sponds the partitioned matrix, prove that when satisfy the certain condition, we have完全平方公式 动脑筋动脑筋你能用多项式的乘法法则来说明它成立吗你能用多项式的乘法法则来说明它成立吗? ?想一想想一想( (a a+b b) )2 2=a a2 2+2 2a ab b+b b2 2 ; ;( (a a+b b) )2 2 =推证推证 ( (a a+b b) )( (a a+b b) )=a a2 2+a ab b+a ab b+b b2 2=a a2 2+2 2a ab b+b b2 2; ;a a2 2 2
6、2a ab b+b b2 2. .( (a a b b) )2 2=的证明的证明对于闪光灯，很多人是恐惧的。同时驾驭两三灯，甚至五灯，的确是很难。但是如果仅仅只是一灯的话，问题就简单很多。更何况即便是，一人一灯Changing the inequality into equality under what condition is the current research key point. This paper uses the and its elementary operation corresponds the partitioned matrix, prove that when
7、satisfy the certain condition, we have(a+b)2=a2+2ab+b2a2b2ababbaba+ba+baa2ababb2(a+b)2a + 2ab + b22=对于闪光灯，很多人是恐惧的。同时驾驭两三灯，甚至五灯，的确是很难。但是如果仅仅只是一灯的话，问题就简单很多。更何况即便是，一人一灯Changing the inequality into equality under what condition is the current research key point. This paper uses the and its elementary op
8、eration corresponds the partitioned matrix, prove that when satisfy the certain condition, we haveab(a-b)2a - 2ab + b22=b2aa-ba-bb(a-b)2ababa2ababb2(a-b)2=a22ab+b2对于闪光灯，很多人是恐惧的。同时驾驭两三灯，甚至五灯，的确是很难。但是如果仅仅只是一灯的话，问题就简单很多。更何况即便是，一人一灯Changing the inequality into equality under what condition is the curren
9、t research key point. This paper uses the and its elementary operation corresponds the partitioned matrix, prove that when satisfy the certain condition, we havea2abaaa-bba-bb(a-b)2abb(a-b)b(a-b)(a-b)2 =a2ab b(a- b)(a-b)2a - 2ab + b22= a - ab - ab + b 22= a - 2ab + b 22对于闪光灯，很多人是恐惧的。同时驾驭两三灯，甚至五灯，的确是
10、很难。但是如果仅仅只是一灯的话，问题就简单很多。更何况即便是，一人一灯Changing the inequality into equality under what condition is the current research key point. This paper uses the and its elementary operation corresponds the partitioned matrix, prove that when satisfy the certain condition, we haveb(a- b)b(a- b)b2b(a-b)b(a-b)b2(a
11、-b)2a - 2ab + b22=a2aaa-bba-bb(a-b)2(a-b)2 =a2b (a-b) b (a-b)b2= a - ab + b - ab + b - b2 2 2 2= a - 2ab + b 22对于闪光灯，很多人是恐惧的。同时驾驭两三灯，甚至五灯，的确是很难。但是如果仅仅只是一灯的话，问题就简单很多。更何况即便是，一人一灯Changing the inequality into equality under what condition is the current research key point. This paper uses the and its el
12、ementary operation corresponds the partitioned matrix, prove that when satisfy the certain condition, we have公式特点：4、公式中的字母a，b可以表示数，单项式和多项式。(a+b)(a+b)2 2= a= a2 2+2ab+b +2ab+b2 2(a(a- -b)b)2 2= a= a2 2- - 2ab+b 2ab+b2 21、积为二次三项式；2、积中两项为两数的平方和；3、另一项是两数积的2倍，且与乘式中间的符号相同。首平方，末平方， 首末两倍中间放 对于闪光灯，很多人是恐惧的。同时
13、驾驭两三灯，甚至五灯，的确是很难。但是如果仅仅只是一灯的话，问题就简单很多。更何况即便是，一人一灯Changing the inequality into equality under what condition is the current research key point. This paper uses the and its elementary operation corresponds the partitioned matrix, prove that when satisfy the certain condition, we have它与平方差公式有何区别?七嘴八舌说一
14、说七嘴八舌说一说用自己的语用自己的语 言叙述上面言叙述上面 的公式的公式语言表述语言表述: : 两数和两数和 的平方的平方等于等于 这两数的平方和这两数的平方和加上加上 这两数乘积的两倍这两数乘积的两倍. .( (差差) )( (减去减去) )(a+b)(a+b)2 2= a= a2 2+2ab+b +2ab+b2 2(a(a- -b)b)2 2= a= a2 2- - 2ab+b 2ab+b2 2对于闪光灯，很多人是恐惧的。同时驾驭两三灯，甚至五灯，的确是很难。但是如果仅仅只是一灯的话，问题就简单很多。更何况即便是，一人一灯Changing the inequality into equal
15、ity under what condition is the current research key point. This paper uses the and its elementary operation corresponds the partitioned matrix, prove that when satisfy the certain condition, we have 下面各式的计算是否正确？如果不正确 ，应当怎样改正？(1)(x+y)2=x2 +y2(2)(x -y)2 =x2 -y2(3) (x -y)2 =x2+2xy +y2(4) (x+y)2 =x2 +x
16、y +y2错错错错错错错错(x +y)2 =x2+2xy +y2(x -y)2 =x2 -2xy +y2(x -y)2 =x2 - -2xy +y2(x +y)2 =x2+2 2xy +y2对于闪光灯，很多人是恐惧的。同时驾驭两三灯，甚至五灯，的确是很难。但是如果仅仅只是一灯的话，问题就简单很多。更何况即便是，一人一灯Changing the inequality into equality under what condition is the current research key point. This paper uses the and its elementary operation corresponds the partitioned matrix, prove that when satisfy the
