x_(1)=1-(2/(1+sqrt(5)))=1+sqrt(5)-2)/(1+sqrt(5))=(sqrt(5)-1)/(sqrt(5)+1) f(x_(1))=100*((sqrt(5)-1)/(sqrt(5)+1) - 1/5)^2=... x_(2)=0+ (1/(1+sqrt(5)))=1-sqrt(5)/(1-5)=sqrt(5)-1)/4 f(x_(2))=