Analysis and Approaches for IBDP Maths Ebook 1 | Page 40

Your Practice Set – Analysis and Approaches for IBDP Mathematics
Exercise 11
1. Let
2
f ( x) � 2x �8x
� 7 and g( x) �x
� 17 , for x� .
(a) Find f (6) .
(b) Find ( g f )( x ).
(c) Solve ( g f )( x) � 0.
[2]
[2]
[3]
2. Let
2
f ( x) � x � 2x
� 5 and g( x) �x
� 1, for x� .
(a) Find f ( � 2) .
(b) Find ( f g)( x ).
(c) Solve ( f g)( x) � 0.
[2]
[2]
[3]
3. Let
f ( x)
3
� x and g( x) 3x
4
� � , for x� .
(a) Find ( g f )( x ).
(b) Find ( g f )(3) .
(c) Solve ( g f )( x) � 1025 .
[2]
[2]
[2]
4. Let f ( x) �5x
� 1 and
g( x)
4
� x , for x� .
(a) Find ( f g)( x ).
(b) Find ( f g)( � 3) .
(c) Solve ( f g)( x) � 1281.
[2]
[2]
[3]
32
SE Production Limited