docs: public static BigComplex sqrt(BigComplex x, MathContext mathContext) {
  		// https://math.stackexchange.com/questions/44406/how-do-i-get-the-square-root-of-a-complex-number
  		MathContext mc = new MathContext(mathContext.getPrecision() + 4, mathContext.getRoundingMode());
  
  		BigDecimal magnitude = x.abs(mc);
  
  		BigComplex a = x.add(magnitude, mc);
  		return a.divide(a.abs(mc), mc).multiply(BigDecimalMath.sqrt(magnitude, mc), mc).round(mathContext);
  	}