Lim x->4 (x-4/akar x-2)...

= lim x->4 x-4/√x-2 × √x-2/√x-2
= lim x-> 4 (x-4)(√x-2) /x-2
= (4-4)(√4-2)/4-2
= 0 x √2 /2
= 0/2
= 0