Question

先化简，后求值a-1分之2a+2 ÷（a+1） +a²-2a+1分之a²-1 其中a=根号3 +1

Answer 1

解：原式=[(2a+2)/(a-1)]÷(a+1)+[(a+1)(a-1)]/(a-1)^2
=2/(a-1)+(a+1)/(a-1)
=(a+3)/(a-1)
=(√3+1+3)/(√3+1-1)
=(√3+4)/√3
=1+4√3/3
(1加3分之4倍根3）