Cho a,b,c>0 thỏa mãn căn ab + căn bc + căn ca =1 tính A=căn a - căn b/ 1+c + căn b - căn c/1+a + căn c - căn a/1+b?

By Trang Ánh Nam -

Cho a,b,c>0 thỏa mãn căn ab + căn bc + căn ca =1 tính A=căn a - căn b/ 1+c + căn b - căn c/1+a + căn c - căn a/1+b?

Giải:

Cho a,b,c> thỏa mãn , tính

Ta có: 

1+c

=

1+a=

=

1+b=

=


Thay vào biểu thức của A : 

=

=

=0

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