--- I have no idea, because I _________ it yet.
A:didn't read
B:don't read
C:won't read
D:haven't read
一个三角形的三边长分别为1、k、4,则化简|2k-5|-k2-12k+36的结果是( )
设函数f(x)的图象关于点(1,2)对称,且存在反函数f﹣1(x),f (4)=0,则f﹣1(4)=____
下列运算正确的是( )