题目：1.用洛必达法则求下列极限:-|||-(1) lim _(xarrow 0)dfrac ({e)^x-cos x}(sin x)-|||-(2) lim _(xarrow 0)dfrac (tan x-x)(x-sin x);-|||-(3) lim _(xarrow {0)^+}dfrac (ln 7 x)(ln 2 x 2x)-|||-(4) lim _(xarrow +infty )dfrac (dfrac {pi )(2)-arctan x}(dfrac {1)(2)}-|||-(5) lim _(xarrow dfrac {pi )(2)}dfrac (ln sin x)({(pi -2x))^2}-|||-(6) lim _(xarrow dfrac {pi )(2)}dfrac (tan x-5)(sec x+4)-|||-(7) lim _(xarrow 0)(dfrac (1)(x)-dfrac (1)({e)^x-1});-|||-(8) lim(sec x-tanx);-|||-→π/-|||-(9)limx cot2x:-|||-(10) lim _(xarrow 0)(x)^2(e)^dfrac (1{{x)^2}}-|||-(11) lim _(xarrow infty )f((e)^dfrac (1{x)}-1);-|||-(12) lim _(xarrow infty )(x)^tan x;-|||-(13) lim _(xarrow 0)((cos x))^dfrac (1{x)};-|||-(14) lim _(xarrow 0)((1+sin x))^dfrac (1{x)}.