乘法公式是初一代数的重点内容，必须认真学好，同时要注意拓广和加深．在复习中要突出一个“用”字，掌握一个“变”字．那么怎样用乘法公式呢？一、化成标准形式，正用公式待解题目不是公式的标准形式时，必须化成标准形式，搞清公式中。和b的相应项，能熟练正m公式．例1计算 The multiplication formula is the key content of the first generation number. It must be carefully studied. At the same time, attention must be paid to broadening and deepening. In the review, we must highlight a “use” word and master a “change” word. So how to use multiplication formula? I. Forming into a standard form. When the formula to be solved with the formula is not the standard form of the formula, it must be converted into a standard form to clarify the formula. And the corresponding term of b, can master positive m formula. Example 1 Calculation