Find the fifth roots of 243(cos 240° + i sin 240°).

Question

amistre64 · Answer

^5 the outside and *5 the innards

amistre64 · Answer

err,  thats 1/5,  not 5

anonymous · Answer

its still confusing to me

amistre64 · Answer

[ k (cos a + i sin a) ]^n

k^n  (cos na + i sin na)

amistre64 · Answer

243(cos 240° + i sin 240°) ^(1/5) , for 5th roots

243^(1/5) (cos 240°/5 + i sin 240°/5)

amistre64 · Answer

might have to cycle thru 1/5  2/5  3/5  4/5  5/5  to determine all the 5th roots

amistre64 · Answer

there seems to be an exponential form as well, but thats just confusing me to read :/

anonymous · Answer

i get that the first is (cos50+isin50)

amistre64 · Answer

essentially, you are dividing a circle into 5 equal portions:  360/5 = 72

and then rotating your starting angle by 72 to get 5 complex values all together

amistre64 · Answer

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