(根号A^2 +A根号B)/(AB-B^2 )-(A+根号AB +B)/(A根号A -B根号B)怎么化简?
问题描述:
(根号A^2 +A根号B)/(AB-B^2 )-(A+根号AB +B)/(A根号A -B根号B)怎么化简?
B^2=B²
答
(根号A^2 +A根号B)/(AB-B^2 )-(A+根号AB +B)/(A根号A -B根号B)
=A(1+根号B)/(AB-B^2)-(A+根号AB +B)/[(根号A)^3-(根号B)^3]
=A(1+根号B)/(AB-B^2)-(A+根号AB +B)/[(根号A-根号B)(A+根号AB +B)]
=A(1+根号B)/(AB-B^2)-1/(根号A-根号B)
=A(1+根号B)/[B(A-B)]-(根号A+根号B)/(A-B)
=[A(1+根号B)-B(根号A+根号B)]/(A-B)
=(A-B根号B)/(A-B)