What is the square root of the imaginary number i?

Let's suppose that (0+1i)0.5 = x+iy, where x and y are both real numbers. This is the most general form of a complex number. Now let's square both sides. This gives 0+1i = x2+2i xy - y2. We will equate real and imaginary parts of this equation to solve for the real numbers x and y. Equating real parts gives x2 = y2 (Equation 1). Equating imaginary parts gives xy=0.5 (Equation 2). Now we will substitute x = 0.5/y into equation 1. This gives us (0.5/y)2 = y2. Multiplying through by y2 results in the following solution for y: y4 = 0.52, so that y = 0.51/2. Then x = 0.5/0.51/2 which gives us that x = y = 0.51/2. So the square root of i is the complex number 0.51/2+0.51/2i.

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Answered by George D. MAT tutor

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