algebra problem help!?

👨🏻‍🏫 學術台數學

[匿名]

2009-12-22 3:28 pm

which expression os equivalent to.. i^55

1) 1 ................. 2). -1

3). i .....................4) -i

回答 (3)

Iggy Rocko

2009-12-22 3:35 pm

✔ 最佳答案

i^1 = i
i^2 = -1
i^3 = -i
i^4 = 1
Using the above,
i^55 =
i^52(i^3) =
(i^4)^13(i^3) =
1^13 (-i) =
-i

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An ESL Learner

2009-12-22 4:10 pm

i^55
= (i^2)^27 * i
= -1 * i
= -i
(option 4)

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[匿名]

2009-12-22 3:40 pm

i^55 = i x i^2 x i^52 = i x -1 x 1 = -i (any powers of i divisible by 4 = 1)
So answer is 4)

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