Answer :

To simplify [tex]\( i^{38} \)[/tex], we can use properties of the imaginary unit [tex]\( i \)[/tex]. Recall that:

[tex]\[ i = \sqrt{-1}, \quad i^2 = -1, \quad i^3 = -i, \quad i^4 = 1 \][/tex]

The powers of [tex]\( i \)[/tex] cycle every 4 terms:
[tex]\[ i^1 = i, \quad i^2 = -1, \quad i^3 = -i, \quad i^4 = 1, \quad i^5 = i, \quad \text{and so on} \][/tex]

Given that every 4th power of [tex]\( i \)[/tex] returns to 1, we can reduce the exponent modulo 4 to simplify our calculation. Since we are looking to simplify [tex]\( i^{38} \)[/tex]:

1. Compute the exponent modulo 4:
[tex]\[ 38 \mod 4 = 2 \][/tex]

2. This means [tex]\( i^{38} \)[/tex] simplifies to [tex]\( i^2 \)[/tex]:
[tex]\[ i^{38} = i^{2} \][/tex]

3. From the properties of [tex]\( i \)[/tex], we know:
[tex]\[ i^2 = -1 \][/tex]

Thus, the simplified form of [tex]\( i^{38} \)[/tex] is:
[tex]\[ -1 \][/tex]

Therefore, [tex]\( i^{38} = -1 \)[/tex].