limx→1√5x−4−√xx2−1
Rationalising the numenator
=limx→1(√5x−4−√x)(x−1)(x+1)×(√5x−4+√x)(√5x−4+√x)
=limx→1((5−4)−x)(x−1)(x+1)(√5x−4+√x)
=limx→14(x−1)(x−1)(x+1)(√5x−4+√x)
=limx→14(x+1)(√5x−4+√x)
=4(1+1)(√5−4+√1)
=42(1+1)
=44=1
limx→1√5x−4−√xx−1
limx→1√5x−4−−√xx3−1