limx→1√5x−4−√xx−1
Rationalising the numenator
=limx→1(√5x−4−√x)x−1×(√5x−4+√x)(√5x−4+√x)
=limx→1((5x−4)−x)(x−1)(√5x−4+√x)
=4limx→1(x−1)(x−1)(√5x−4+√x)
=4limx→11√5x−4+√x
=4×1√5−4+√1
=4×1√1+√1
=42=2
limx→1√5x−4−−√xx3−1
limx→1√5x−4−√xx2−1