`(2x)/(1+x^(2))`

If f(x)=x^(2)+(x^(2))/(1+x^(2))+(x^(2))/((1+x^(2))^(2))+…… upto, oo , then

f(x)=(x^(2))/(1+x^(2))+(x^(2))/((1+x^(2))^(2))+(x^(2))/((1+x^(2))^(3))+............oo is f(x) continuous at the origin? Give reasons for your answer.

The derivative of tan^(-1)2(x)/(1-x^(2)) with respect to sin^(-1)2(x)/(1+x^(2)), is

If f(x)=x^(2)+(x^(2))/(1+x^(2))+(x^(2))/((1+x^(2))^(2))+...+(x^(2))/((1+x^(2))^(n))+... then at x=0,f(x) has no limit (b) is discontinuous is continuous but not differentiable (d) is differentiable

If f(x)=x^(2)+(x^(2))/(1+x^(2))+(x^(2))/((1+x^(2))^(2))+...oo term then at x=0,f(x)

int(2x^(2)(1+2x^(2)))/((1+x^(2)+x^(4))^(2))dx is equal to

int(2x^(2)(1+2x^(2)))/((1+x^(2)+x^(4))^(2))dx is equal to