limx→1√5x−4−−√xx3−1
Rationalising the numenator
=limx→1(√5x−4−√x)(x−1)(x2+1+1)×(√5x−4+√x)(√5x−4+√x)
=limx→1(5x−4−x)(x−1)(x2+1+x)(√5x−4+√x)
=limx→14(x−1)(x−1)(x2+x+1)(√5x−4+√x)
=4(1+1+1)(√5−4+√1)
=43(1+1)=43×2=23
limx→1√5x−4−√xx−1
limx→1√5x−4−√xx2−1