举报
swallow570415
A=(x+1)^(1/3) B=(x-1)^(1/3) (X+1)^(2/3)+2(X^2-1)^(1/3)+(X-1)^(2/3)=A^2+2AB+B^2=(A+B)^2 f(1)=1/2^(2/3) f(3)=1/[2^(1/3)+4^(1/3))^2=1/[2^(2/3)(1+2^(1/3))^2] f(5)=1/[4^(1/3)+6^(1/3)]^2=1/[2^(2/3)(2^(1/3)+3^(1/3)^2] ... f(1)+f(3)+...+f(99)=[99/2^(2/3)] *[1+1/(1+2^(1/3))^2+ 1/(2^(1/3)+3^(1/3))^2+...+1/(49^(1/3)+50^(1/3))^2]没法继续