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I’m very confused with this question, I tried to do it but I just have slight feeling I got this wrong and I want to double check make sure my answer is correct. Would you please me help me thank you very much

I’m very confused with this question, I tried to do it but I just have slight feeling-example-1
User Edharned
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1 Answer

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The powers of the imaginary number i have four possible values: 1, i, -1, and -i. Let's see some examples:

i⁰ = 1 (any number with the exponent 0 equals 1)

i¹ = i (any number with the exponent 1 is the number itself)

i² = -1 (this follows from the definition of the imaginary number, the square root of -1)

i³ = i² * i = -1 * i = -i

Now, the results start to repeat from 1 to -i:

i⁴= i² * i² = (-1) * (-1) = 1

i⁵ = i⁴ * i = 1 * i = i

i⁶ = i * i⁵ = i * i = i² = -1

i⁷ = i⁶ * i = -1 * i = -i

From that, we can follow the steps below to find the value of a power of i:

• divide the exponent by 4;

,

• if the rest of the division is 0, then the power equals ,i⁰ = 1,;

,

• if the rest of the division is 1, then the power equals ,i¹ = i,;

,

• if the rest of the division is 2, then the power equals ,i² = -1,;

,

• if the rest of the division is 3, then the power equals ,i³ = -i,.

So, for the power i⁶⁴⁹, the exponent is 649. Following the steps above, we find:

• 649/4, has a quotient of 162 and the, rest 1,. Therefore:

i⁶⁴⁹ = i¹ = i

Thus, i⁶⁴⁹ equals i.

User Brendon Crawford
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