初二数学题-填空
(1)若a+1/a=2,那么a^2+1/a^2=(___),a^4+1/a^4=(___).(2)若a+1/a=3,a^2+1/a^2=(___),a^4+1/a^4=(___).(3)若a+1/a=n,那么a^2+1/a^2=(___),a^4+1/a^4=(___).