2 , if
0
( )
0,
if 0
1
4 , if
>1
x
x
f x
x
x
x
<
=
≤
≤


16 2, if
1
( )
2 , if
1
1
2,
if
1
x
f x
x
x
x
−
≤ −
=
− <
≤

>

17 Find the relationship between a and b so that the function f defined by
1, if
3
( )
3, if
3
ax
x
f x
bx
x
+
≤
= 
+
>

is continuous at x = 3 18