共50条信息
如图,已知等腰直角三角形\(ABC\),点\(P\)是斜边\(BC\)上一点\((\)不与\(B\),\(C\)重合\()\),\(PE\)是\(\triangle ABP\)的外接圆\(⊙O\)的直径.
\((1)\)求证:\(AP=AE\);
\((2)\)若\(⊙O\)的直径为\(5\),求\(PC^{2}+PB^{2}\)的值.
设\(I\)是\(\triangle ABC\)的内心,\(O\)是\(\triangle ABC\)的外心 ,\(∠A=80^{\circ}\),则\(∠BIC=\)_________,\(∠BOC=\)_________。
将正方形\(ABCD\)绕点\(A\)按逆时针方向旋转\(30^{\circ}\),得正方形\(AB_{1}C_{1}D_{1}\),\(B_{1}C_{1}\)交\(CD\)于点\(E\),\(AB=\sqrt{3}\),则四边形\(AB_{1}ED\)的内切圆半径为( )
如图,在\(Rt\triangle ABC\)中,\(∠C=90^{\circ}\),\(∠B=58^{\circ}\),内切圆\(O\)与边\(AB\)、\(BC\)、\(CA\)分别相切于点\(D\)、\(E\)、\(F\),则\(∠DEF\)的度数为 \({\,\!}^{\circ}.\)
如图为\(4×4\)的网格图,\(A\)、\(B\)、\(C\)、\(D\)、\(O\)均在格点上,点\(O\)是( )
已知点\(O\)是\(\triangle \)\(ABC\)的内心,\(∠\)\(A\)\(=50^{\circ}\),则\(∠\)\(BOC\)的大小为______.
如图,点\(O\)是边长为\(8\sqrt{3}\)的等边\(\triangle ABC\)的内心,将\(\triangle OBC\)绕点\(O\)逆时针旋转\(30^{\circ}\)得到\(\triangle OB′C′\),\(B′C′\)交\(BC\)于点\(D\),交\(AC\)于点\(E\),则\(DE\)的长为________.
下列事件中是必然事件的是 ( )
进入组卷