Given the coefficient of in the expansion of is 189,show that the value of n = 7.）

分类: 作业答案 • 2021-12-28 10:38:37

问题描述：

Given the coefficient of in the expansion of is 189,show that the value of n = 7.）
我知道意思嗄～^^ coeffient后面是X^2;of后面是(1+3x)^n

答

给膨胀系数赋值189时,显示结果是n等于7.
请参考选用.