What value of x should we take to obtain the new transformed equation?

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Answer 1 · 2018-02-28T17:05:27

Answer is (2).

We have that #alpha,beta# and #gamma# are the roots of #x^3-x-1=0#.

Let #g(t)=(1+t)/(1-t)=y#,

then we are seeking a function whose roots are #g(alpha),g(beta)# and #g(gamma)#.

Now as #alpha,beta# and #gamma# are roots of #x^3-x-1=0#,

#g(alpha),g(beta)# and #g(gamma)# are roots of #t^3-t-1=0#,

where #(1+t)/(1-t)=y#, i.e. #1+t=y-ty# or #t(y+1)=y-1#

or #t=(y-1)/(y+1)#

Hence, answer is (2).