Q.

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


Ans.

(2)

f(0)=limx→0tan(tanx)–sin(sinx)–tanx+tanx–sinx+sinxtanx–sinx

=limx→0tan(tanx)–tanxtan3x×tan3xx3+tanx–sinxx3+sinx–sin(sinx)sin3x×sin3xx3tanx–sinxx3

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