In any sequence of $n$ nonzero numbers, a pair of consecutive terms with opposite signs represents a sign change. For example, the sequence -2, 3,-4, 5 has three sign changes. Does the sequence of nonzero numbers $s_1,s_2,\ldots, s_n$ have an even number of sign changes?

为什么这里会被遮住？

不再显示

GMAC主张了此真题版权，我们仅能展示部分内容以供查询定位。获取使用帮助请添加微信小助手：

1. $s_k = (-1)^k$ for all positive integers $k$ from 1 to $n$.

2. $n$ is odd.