题目

下列各式中，能用完全平方公式因式分解的是（ ）A. B. C. D. 答案：【答案】D【解析】根据完全平方公式的形式即可判断.D. =(2x)2-2×2x×3+32=(2x-3)2故选D. —Mum, I have got a headache.— You’d better go out and take a walk. You       in front of the TV too long.  [     ]A. have been sittingB. are sittingC. sitD. sat