00:01
Hello students, we have given that z equal to minus 8 plus 8i into root of 3.
00:07
We write it in the polar form as r equal to square root of 64 plus 64 into 3 which is equal to 8 root 4 which is equal to 16.
00:20
So we have tan theta equal to 8 root 3 divided by minus 8 which implies minus root 3.
00:30
So theta will be equal to pi minus pi by 3 which is equal to 2 pi by 3.
00:36
We have z equal to r2 into cos of theta plus i into sin theta.
00:45
So this is z equal to 16 into cos of 2 pi by 3 plus i into sin of 2 pi by 3 equal to 16 e to the power i into 2 pi by 3.
01:00
Now we know that e to the power i theta equal to cos theta plus i into sin theta.
01:11
So in general for nth root we have pi equal to theta plus 2 pi k divided by n where k is 0, 1, 2 and so on.
01:37
Now the fourth root means n is equal to 4 and k will be equal to 0, 1, 2, 3.
01:45
So pi is equal to 2 pi by 3 plus 2 pi k whole divided by 4...