Find square root of-15 -8i

Asked by rajdeepdehury | 18th Feb, 2019, 02:01: AM

Expert Answer:

Let √(-15 - 8i) = x + yi
-15 - 8i = (x + iy)2
-15 - 8i = x2 + 2xyi + i2y2
-15 - 8i = x2 + 2xyi - y2
-15 - 8i = x2 y+ 2xyi
Comparing we get 
x2 - y2 = -15 ....(i)
2xy = -8 
xy = -4 ....(ii)
solving (i) and (ii) we get values of x and y and put it in x + iy
we get the square roots of -15 - 8i

Answered by Sneha shidid | 18th Feb, 2019, 09:28: AM