Bayangan garis y=2x+3karena rotasi yg berpusat di(0,0) sebesar π/2 radian

jawab

y  = 2x + 3  rotasi (O, 90°)→ x = -2y + 3
atau 2y = - x + 3



[tex] \left[\begin{array}{ccc}x'\\y'\end{array}\right] \, = \left[\begin{array}{ccc}cos 90&- sin 90\\sin90&cos 90\end{array}\right]\, \left[\begin{array}{ccc}x\\y\end{array}\right]\\ \left[\begin{array}{ccc}x'\\y'\end{array}\right]\, = \left[\begin{array}{ccc}0&-1\\1&0\end{array}\right]\, \left[\begin{array}{ccc}x\\y\end{array}\right]\\ \left[\begin{array}{ccc}x'\\y'\end{array}\right] \, = \left[\begin{array}{ccc}-y\\x\end{array}\right] \\ x = y' \, dan \, y\, = -x'\\ bayangan \, x = -2y + 3 [/tex]