a) lim x--->0.5- sqrt((x+2)/(x+1))
b) lim x--->1+ sqrt((x-1)/(x+2))
Btw, the 0.5 is a lower limit (thats why there's a negative sign next to it) and the 1 with the + next to it means upper limit, you know!
In the first case you can just substitute the limiting value of x in the expression as it is a point of contiuity of the expression.
For the second you can do the same as the expression is continuous from the right at the limiting value of x and you are approaching from the right.
CB