5−√105+√10−5+√105−√10
Multiplying both numerator and denominator by the rationalising factor of the denominators, we have
=5−√105+√10×5−√105−√10−5+√105−√10×5+√105+√10
[2]
=(5−√10)225−√(10)2−(5+√10)225−√(10)2
=25−10√10+1015−25+10√10+1015
[2]
=25−10√10+10−25−10√10−1015
=−20√1015
=−43√10
[1]