A:磷脂
B:固醇
C:脂肪
D:糖原
把二次函数y=-14x2-x+3用配方法化成y=a(x-h)2+k的形式( )
Tom can play _______ basketball but he can't play ________ guitar.
先化简,再求值:(1+x)(1﹣x)+x(x+2)﹣1,其中x=12.