Question

( f(x)=frac{x}{1+x^{2}} )
( y=frac{x}{1+x^{2}} )
( y x^{2}+y-x=0 )
( operatorname{as} x in R quad ) So ( quad 0 geq 0 )
( 1-4 y^{2} geq 0 )
( -4 y^{2} geq-1 )
( y^{2} leq 1 / 4 )
( y leqslantleft[-frac{1}{2}, frac{1}{2}right] )
Remge

# Letf:R → Rbe defined by f(x)= 2,XER. Then the range of fis: 02 (2) R-E-1, 1) (3)R-21 (4) 6–1, 1) - {0} Let K be the set of all real values of x where the function f(x)=sin(x – ]x] + 2(x - 1) cos |x| is not differentiable. Then the set K is equal to: (1) 0 (empty set) (2) {n} (3) {0} (4) {0, T}

Solution