计算:- 根号42乘以根号6乘以(-1/7根号7)
=[√6*7*6)*√7]/7
=[6√(7*7)]/7
=(6*7)/7
=6
(7-4倍根号3)平方2007乘以(-7-4倍根号3)平方2008
=(7-4√3)^2007*(7+4√3)^2008
=(7-4√3)^2007*(7+4√3)^2007*(7+4√3)
=[(7-4√3)(√7+4√3)]^2007*(7+4√3)
=(49-48)^2007*(7+4√3)
=7+4√3
计算:- 根号42乘以根号6乘以(-1/7根号7)
=[√6*7*6)*√7]/7
=[6√(7*7)]/7
=(6*7)/7
=6
(7-4倍根号3)平方2007乘以(-7-4倍根号3)平方2008
=(7-4√3)^2007*(7+4√3)^2008
=(7-4√3)^2007*(7+4√3)^2007*(7+4√3)
=[(7-4√3)(√7+4√3)]^2007*(7+4√3)
=(49-48)^2007*(7+4√3)
=7+4√3