SOS！！！菜鸟求助哦~~

momohere88

FOR a finite sequence of nonzero numbers,the number of variations in sign is defined as the number of pairs of consecutive terms of the sequence for which the product of the two consecutive terms is negative.what is the number of variations in sign for the sequence?

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alice2292

For a finite sequence of nonzero numbers, the numbers fo variations in signs is definfed as the number of pairs of consecutive terms of the sequence for which the product of the 2 consecutive terms is negetive .What is the number of variation in sign for the sequences 1,-3,2,5,-4,-6

a. one
b. two
c. three
d. four
e. five

C