Find the set of points that the following function is continuous at them.

f(x)= { √(5-x) -2 if x < 1 , (2x-1 + In(x)) / (x-25) if x>1, -1/24 if x=0

√(5-x) is defined for x<5

so, using x<1 works there

lnx is defined for x>0
so, x>1 works there
except where x=25

So, f(x) is defined and continuous on

(-∞,1)U(0)U(1,25)U(25,∞)