http://ascklee.org/

1

Solutions to Revision Exercise 13 (Ho Soo Thong & Khor Nyak Hiongs Panpac Additional Mathematics)

Solved by: Dr Lee Chu Keong (ascklee@gmail.com)

http://ascklee.org/CV/CV.pdf

http://ascklee.org/

2

Revision Exercise 13 This PDF file only contains solutions. For the questions, please refer to Ho Soo Thong and Khor Nyak Hiongs textbook, Additional Mathematics. Question 1(a)

Multiplying throughout by 4:

( )

Substituting ( ) into

Multiplying throughout by 4:

( )

( ) ( ) eliminates to give:

(

)

http://ascklee.org/

3

So,

and

Question 1(b)(i)

Let ( )

( )

( )

Question 1(b)(ii)

Let ( )

( )

Question 1(c)

( )

( ) ( )

( )

(

)

( )

http://ascklee.org/

4

To obtain the gradient of the normal to the curve, we use

At ,

Equation of the normal:

Question 2(a)

( )

( ) ( )

( )

At ,

( )

Equation of tangent:

( )

Question 2(b)

http://ascklee.org/

5

When ,

( )( )

or

When ,

( )

Equation of tangent:

When ,

( )

Equation of tangent:

( )

( )

Question 2(c)

( ) ( ) ( ) ( )

( )

( )

( )

( )

( )

Question 3(a)

Length of one side

Length of the other side,

http://ascklee.org/

6

If the length of one side is increasing, the length of the other side must decrease to keep the area constant at 50 cm2.

(

)

The other side ( ) is decreasing at a rate of . Question 3(b)

At the turning point,

Coordinates of turning point are ( ). Question 4(a)

http://ascklee.org/

7

When ,

Question 4(b)

Question 6(a)(i)

( ) ( )

( )

( )

( )

( )

( )

Question 6(a)(ii)

(

)

( ) ( )

(

)

( ) ( )

( )( )

http://ascklee.org/

8

The latest version of this file can be

downloaded from OpenlySolved.org.

http://openlysolved.org/