Ask your own question, for FREE!
Mathematics 11 Online
OpenStudy (anonymous):

Can someone explain to me the powes of i?

hartnn (hartnn):

you know whats i ?

OpenStudy (anonymous):

variable?

hartnn (hartnn):

you are in imaginary numbers topic , right ? so, \(\large i=\sqrt{-1}\) heard of it ?

OpenStudy (anonymous):

Yeah i i heard of it

hartnn (hartnn):

so, whats i^2 =... ?

OpenStudy (anonymous):

1 ?

hartnn (hartnn):

no! \(i=\sqrt {-1}\) squaring both sides, \(i^2=-1\) got this ?

OpenStudy (anonymous):

ok

hartnn (hartnn):

to get i^3, just multiply i on both sides i^3=-i ok?

OpenStudy (anonymous):

ohh ok soo like i^3(-1) or somthing like that?

hartnn (hartnn):

what ? i^3 = -i

OpenStudy (anonymous):

sorry its really new for me kinda lost

hartnn (hartnn):

i = sqrt (-1) so i^2 = -1 i^3 = i*i^2 = i*-1 =-i which part did u not get ?

OpenStudy (anonymous):

if i wanted to find i^4= i^3*i=i*-1 or i^2*i^2=i^2*-1?

hartnn (hartnn):

both way works but use that i^3=-i

hartnn (hartnn):

so, i^4 = i^2*i^2 = -1 *-1 = 1 got this ?

OpenStudy (anonymous):

Ohh ok i^5= i^2*i*3= -1*-i=i?

hartnn (hartnn):

corrct! :)

OpenStudy (anonymous):

What if i were to do a number like i^36?

hartnn (hartnn):

we note the pattern, like i^4 =1, we will get i^8 also =1 i^12 = 1 , i^16 =1 and so on... do u notice a pattern ?

OpenStudy (anonymous):

Yes soo like i^3=-i and i^9= -1 and every like multypul of 3 will be -i

hartnn (hartnn):

nopes, that worked for multiples of 4 i^3 = i^7 = i^11 =i^15 =... = -i means if the exponents are \(\huge 4 \) apart, the value is same

hartnn (hartnn):

similarly, i^2=i^6=i^10=...= -1

OpenStudy (anonymous):

ok i see was about to say same thing lol

hartnn (hartnn):

cool, so u now understand ?

OpenStudy (anonymous):

yeah im getting it more and more soo i^36= 1

hartnn (hartnn):

correct! :) can i ask you one ? i^22 = ... ?

OpenStudy (anonymous):

ok -1

hartnn (hartnn):

good! :)

hartnn (hartnn):

want few more ?

OpenStudy (anonymous):

i^2=-1 i^6=-1......22^i=-1 sure yeah

ganeshie8 (ganeshie8):

wat about i^4000000000000001 :)

hartnn (hartnn):

lol, i was trying to be bit lineant and ask him i^1001

hartnn (hartnn):

i^4000000000000001 =... ? i^1001 =.... ? its easy once you get that i^4 =1

hartnn (hartnn):

**** \(\large i^{4n}=1\)

OpenStudy (anonymous):

ლ(゚д゚ლ)

hartnn (hartnn):

for any integer n

ganeshie8 (ganeshie8):

that looks like one of i's lol :P

OpenStudy (anonymous):

just so ik i^5 =i^3*i^2=i?

ganeshie8 (ganeshie8):

first kill the i^4 s

hartnn (hartnn):

i^5 = i^4 * i = i better ?

OpenStudy (anonymous):

ohh haha yes

OpenStudy (anonymous):

i=-1 if it didnt have a right

OpenStudy (anonymous):

or just i

hartnn (hartnn):

what ? i = sqrt -1 i^2=-1

OpenStudy (anonymous):

ohh yeah yeah i frgot

OpenStudy (anonymous):

what questions were u going to throw at me ?

hartnn (hartnn):

i^4000000000000001 =... ? i^1001 =.... ?

hartnn (hartnn):

lets take i^101 first, how would u go on solving this ? you know i^4 =1 , so is i^8, so is i^12 and so on...actually when powers are multiples of 4, we get answer =1 so why not separate a power of 4 from 101 ? 100 divisible by 4 right ? so i^100 = 1 so, i^101 = i^100 *i = 1*i=i got this ?

OpenStudy (anonymous):

ok i see how you got i^100=4 i^101 =?

OpenStudy (anonymous):

ohh waut nvm i^101 =1

hartnn (hartnn):

no....i^100 = 1 because 100 is multiple of 4

OpenStudy (anonymous):

ohh yeah my bad i messed up typeing that how did u get i^101?

hartnn (hartnn):

i^101 is just i^100 times i

OpenStudy (anonymous):

ok ok i^4000000000000001 =... i^400000000000000 *1^1 would i do that

hartnn (hartnn):

i^400000000000000 *i^1 yes! i^400000000000000 *i^1 = 1*i^1 = i

hartnn (hartnn):

wasn't that easy ?

OpenStudy (anonymous):

yeah kinda

hartnn (hartnn):

same way i^1001 = .... ? i promise, this is last :P

OpenStudy (anonymous):

ok i^1000=1*i=i

hartnn (hartnn):

i^1001 = i^1000*i^1 = 1*i =i correct! good work :)

hartnn (hartnn):

i hope you are more confident on this topic now :)

OpenStudy (anonymous):

yes school lesson is really stupid

OpenStudy (anonymous):

Thanks

hartnn (hartnn):

welcome ^_^

Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!
Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!