The fourth roots of 1 are 1, -1, i and -i. We can check this easily. So the correct picture is C (all roots lie at the axis with the coodinates of ±1).
Now, fill out the empty fields at a top of the question. The 1 as a complex number has an angle of 0. So,
the roots are: cos([0 + (2π)*k]/4) + i*sin([0 + (2π)*k]/4), k = 0,1,2,3. (4 pcs)
2π/4 = π/2 = 90° (/4 is from the fourth degree). So,
the roots are: cos(0°+90°k) + i*sin(0°+90°k) = cos(90°k) + i*sin(90°k), k=0,1,2,3.
Content will be erased after question is completed.
Enter the email address associated with your account, and we will email you a link to reset your password.
Forgot your password?