x/y+y/x
=(1/3-2√2)/(1/3+2√2)+(1/3+2√2)/(1/3-2√2)
分母通分后=【(1/3-2√2)²+(1/3+2√2)²】/(1/9-8)
=2(1/9+8)/(1/9-8)
=