z=a+bi,a,b是实数有实数解x是实数x²+ax+bxi+4+3i=0(x²+ax+4)+(bx+3)i=0所以bx+3=0x²+ax+4=0b=-3/xa=-(x²+4)/xa²+b²=(x^4+8x²+25)/x²=x²+25/x²+8>=2√(x²*25...