Question

rationalise
a)1/√5-4​

Answer 1

$1/√5-4×√5+4/√5+4 \\ </p><p>√5+√4/1$

Answer 2

Answer:

conjugate of denominator√5-4 is√5+4.

multiply and divide by√5+4

1/√5-4= 1/√5-4×√5+4/√5+4

=√5+4/(√5)²-4²

=√5+4/5-16

=√5+4/-11