Câu 40:
limx→1x+x2+1x+1=a+b2 (a,b∈Q).\mathop {\lim }\limits_{x \to 1} \frac{{x + \sqrt {{x^2} + 1} }}{{x + 1}} = a + b\sqrt 2 \,\,\left( {a,b \in \mathbb{Q}} \right).x→1limx+1x+x2+1=a+b2(a,b∈Q). Tính a+ba + ba+b.
