=(x2﹣2x﹣3)(x2﹣2x+1)
=(x﹣3)(x+1)(x﹣1)2.
填空:x2+10x+ ____ =(x+ ____ )2.
如图,矩形ABCD的对角线AC和BD相交于点O,过点O的直线分别交AD和BC于点E、F,AB=2,BC=3,则图中阴影部分的面积为( )
To his ____(快乐,喜悦), his son was admitted to a famous university.