Q.

If the function f(x)=tan(tanx)sin(sinx)tanxsinx is continuous at x = 0, then f(0) is equal to ________.         [2025]


Ans.

(2)

f(0)=limx0tan(tanx)sin(sinx)tanx+tanxsinx+sinxtanxsinx

=limx0tan(tanx)tanxtan3x×tan3xx3+tanxsinxx3+sinxsin(sinx)sin3x×sin3xx3tanxsinxx3

=1+(13+16)(13+16)=2.          [From L'Hospital's Rule]