If `(logx)/(b-c)=(logy)/(c-a)=(logz)/(a-b)` prove that
(a) `x^(a)y^(b)z^(c )=1`
(b) `x^(b+c).y^(c+a).z^(a+b)=1`
(c ) `x^(b^(2)+bc+c^(2)`.`y^(c^(2)+ca+a^(2))`.`z^(a^(2)+ab+b^(2))`=1