Because the exponent 200 could be written as 2*100, we'll
calculate first (1+i)^2.
We'll expand the binomial using
the formula:
(a+b)^2 = a^2 + 2ab +
b^2
a = 1 and b = i
(1+i)^2 =
1^2 + 2*1*i + i^2, where i^2 = -1
(1+i)^2 = 1 + 2i -
1
We'll eliminate like
terms:
(1+i)^2 = 2i
Now, we'll
write (1+i)^200 = [(1+i)^2]^100
[(1+i)^2]^100 =
(2i)^100
(2i)^100 =
2^100*i^100
We'll recall the power of
i:
i^2 = -1
i^3 = i^2*i = -1*i
= -i
i^4 = i^2*i^2 = (-1)*(-1) =
1
We'll write 100 as a multiple of
4:
100 = 4*25
i^100 =
(i^4)^25
i^4 = 1
i^100 =1^25 =
1
(1+i)^200 = 2^100 = (2^4)^25 =
16^25
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