Question

Can some one help me. The QN is SIMPLIFY BY RATIONALISING DENOMINATOR.

Answer 1

`(10)/(3)` -
`(2√(7) )/(3)`

Explanation:

Rationalise the denominator by multiplying the numerator/ denominator by the conjugate of the denominator

the conjugate of
`√(7)` + 5 is
`√(7)` - 5, hence

12 / (
`√(7)` + 5) × (
`√(7)` - 5 ) / (
`√(7)` - 5)

= (12
`√(7)` - 60 ) / - 18

=
`(10)/(3)` -
`(2√(7) )/(3)`