SOLUTION: what is i to the 235th power

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Question 26756: what is i to the 235th power
Found 2 solutions by whty89, bmauger:
Answer by whty89(20) About Me  (Show Source):
You can put this solution on YOUR website!
to solve this you need to know the 4 basic powers of i.
i^1=square root of -1=i
i^2=-1
i^3=-i
i^4=1
to find i to any power you just take that number and divide it by 4.
in this case 235/4=58.75
Forget about the whole number, just look at the decimal if the decimal was
.25=i
.50=-1
.75=-i
no remainder equals 1


Answer by bmauger(101) About Me  (Show Source):
You can put this solution on YOUR website!
i, the imaginary square root of -1, follows a pattern when you raise it to various powers.
By definition any number (even this imaginary one) to the 0th power is 1, so:
i%5E0=1
Since any number raised to 1 is itself, we start with:
i%5E1=i
by the definition of i, squaring it gives -1:
i%5E2=-1
taking it to the third power is the same as multiplying -1 (i squared) times i:
i%5E3=-i
and taking it to the forth power is the same as multiplying -1 (i squared) times -1 (i squared):
i%5E4+=+i%5E2+%2A+i%5E2+=+%28-1%29%5E2+=+1
If we multiply this by another i, i raised to the fifth, we start to see the pattern:
i%5E5+=+i%5E4+%2A+i+=+1+%2A+i+=+i
In fact, knowing that i^4=1 means that we can multiply as many i^4 as possible together and still get 1. Example:
i%5E24+=+%28i%5E4%29%5E6+=+1%5E6+=+1
Dividing 235 by 4, we get 58.75 so we have a total of 58 4's we can "cancel". Therefore, in your problem, i^235, we can rewrite 235 as 4*58 + 3. Using laws of exponents i to the 235th can be rewritten as:
i%5E235+=+i%5E%284%2A58%2B3%29
i%5E235+=+%28i+%5E+4%29%5E58+%2A+i+%5E3
i%5E235+=+1%5E58+%2A+%28-i%29
Answer:
i%5E235+=+-i