(t+1)²+(t-1)²=8+4t jie

(t+1)²+(t-1)²=8+4t jie
(t+1)²+(t-1)²=8+4t jie

(t+1)²+(t-1)²=8+4t jie
(t+1)²+(t-1)²=8+4t
t²+2t+1+t²-2t+1=8+4t
t²+t²+2t-2t-4t+1+1-8=0
2t²-4t-6=0
t²-2t-3=0
(t-3)(t+1)=0
t-3=0 或 t+1=0
t=3 或 t=-1