(x^2-2ax+5)+i(x^2+2x-3)=0
虚部为0-->x^2+2x-3=0-->(x-1)(x+3)=0--->x=1 or -3
实部为0-->x^2-2ax+5=0-->x=1:1-2a+5=0--> a=3
x=-3:9+6a+5=0-->a=-7/3
a=3 或-7/3.
(x^2-2ax+5)+i(x^2+2x-3)=0
虚部为0-->x^2+2x-3=0-->(x-1)(x+3)=0--->x=1 or -3
实部为0-->x^2-2ax+5=0-->x=1:1-2a+5=0--> a=3
x=-3:9+6a+5=0-->a=-7/3
a=3 或-7/3.