Question

find constan a and b

Answer 1

\[\lim_{x \rightarrow 0} \frac{ \sqrt{ax+b}-1 }{ x }\] =1

Answer 2

Have you tried rationalizing the fraction?
(multilplying the both the numerator and denominator by [sqrt(ax+b) - 1] )

Answer 3

It's not really rationalizing since it would put a radical in the denominator, but doing that often makes limits easier to solve.

Answer 4

\[\frac{ ax+b-1 }{ x(\sqrt{ax+b}+1) }\]