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f-R-R-g-R-R-f-x-determinant-x-g-x-g-x-x-g-x-determinant-f-x-x-x-f-x-




Question Number 316 by 123456 last updated on 25/Jan/15
f:R→R  g:R→R  f(x)= determinant ((x,(g(x))),((g(−x)),(−x)))  g(x)= determinant (((f(x)),x),((−x),(f(−x))))
f:RRg:RRf(x)=|xg(x)g(x)x|g(x)=|f(x)xxf(x)|
Answered by prakash jain last updated on 21/Dec/14
f(x)=−x^2 −g(x)g(−x)     ...(i)  g(x)=f(x)f(−x)+x^2           ...(ii)  f(−x)=f(x)  g(−x)=g(x)  f(x)=−x^2 −[g(x)]^2   g(x)=x^2 +[f(x)]^2   f(x)+g(x)=[f(x)]^2 −[g(x)]^2 =[f(x)+g(x)][f(x)−g(x))]  f(x)−g(x)=1  f(x)=1+g(x)  1+g(x)=−x^2 −[g(x)]^2   [g(x)]^2 +g(x)+(1+x^2 )=0  g(x)=((−1±(√(1−4(1+x^2 ))))/2)=((−1±(√(−x^2 −3)))/2)  f(x)=1+g(x)=((1±(√(−x^2 −3)))/2)  The solution pair meets all condition except  f(x) and g(x) are not real for any real x.  So given conditons has no solution.
f(x)=x2g(x)g(x)(i)g(x)=f(x)f(x)+x2(ii)f(x)=f(x)g(x)=g(x)f(x)=x2[g(x)]2g(x)=x2+[f(x)]2f(x)+g(x)=[f(x)]2[g(x)]2=[f(x)+g(x)][f(x)g(x))]f(x)g(x)=1f(x)=1+g(x)1+g(x)=x2[g(x)]2[g(x)]2+g(x)+(1+x2)=0g(x)=1±14(1+x2)2=1±x232f(x)=1+g(x)=1±x232Thesolutionpairmeetsallconditionexceptf(x)andg(x)arenotrealforanyrealx.Sogivenconditonshasnosolution.