2007-II-44
答案:C
$\begin{array}{rcl}
a_1 & = & a_2 – 6
… Read $\begin{array}{rcl}
a_1 & = & a_2 – 6
$\
上圖所示為 $y=\sin x^\circ$ 的圖像。透過比較兩幅圖,可知 $y=\sin x^\ci
$\begin{array}{rcl}
\dfrac{x}{\si
$\begin{array}{rcl}
\cos \a
連結 $BC$。考慮 $\Delta ABD$ 及 $\Delta ACB$,
$\begin{array
$\
$\begin{a
$\begin{array}{cl}
= & \dfrac{8}{13} \ti
$\begin{array}{cl}
= & 1 – \dfrac{1