Question 33044
{{{3sqrt(7)}}}/{{{-(1+sqrt(27))}}}
now rationalise the numerator by multipling wit sqrt 7 on both numerator and denominator
{{{3sqrt(7)}}}* {{{sqrt(7)}}}/{{{-(sqrt(7)+sqrt(27)*sqrt(7))}}}
- 3*7/{{{(sqrt(7)+sqrt(27*7))}}}
-21/{{{sqrt(7)+sqrt(169)}}}
-21/{{{sqrt(7)+ 13}}}
now rationalise the denominator by multipling with {{{13 - sqrt(7)}}} to both numertor and denominator
-21 * ({{{13 - sqrt(7)}}})/{{{(13)^2 - (sqrt(7))^2}}}
-21 * ({{{13 - sqrt(7)}}})/169 - 7
-21 * ({{{13 - sqrt(7)}}})/162
-7* ({{{13 - sqrt(7)}}})/54