128k views
2 votes
Find the value of i77.
A) 1
B) i
C) −1
D) −i

2 Answers

3 votes

Answer:

The correct answer is B

Step-by-step explanation: I remember from my algebra 2 class, you divide the powers by 4, and it should give you 194.5. When your decimal is .5 that means it is a positve "i".

User Hoangquyy
by
9.2k points
4 votes

assuming you mean
i^(77) where
i=√(-1)

ok, notice a pattern in the exponent


i^1=i=√(-1)


i^2=-1


i^3=-√(-1)=-i


i^4=1


i^5=i=√(-1)

hum, so it goes 1,2,3,4, then repeats

ok, so every 4, the cycle repeats

how far up is 77 from a multipule of 4?

4*19=76

76 is 1 away from 77

so
i^(77)=(i^(76))(i^1)=


(i^4)^(19)(i)=(1)^(19)i=i

the answer is B

User Parin Parikh
by
8.5k points