FUNCTIONS G2

 

SEQUENCE & SERIES G1

 

The 1st term of an arithmetic progression is 60 and the common difference is 40. Find the nth term

 

solution

 

A1=60, d= 40, n=?

 

An =A1 + (n-1) d

 

An=60 + (n-1)40

 

An=60 + 40n -40

 

An=40n + 60-40

 

An=40n + 20

 

Hence the nth term is An=40n + 20  

 

TRY THIS………………….. 

 

The 1st term of arithmetic progression is 148 and the common difference is 170. Find the nth term

FUNCTIONS G1

 

Find the maximum value of the quadratic equation:7-6t-8t².

 

Solution

 

a=-8, b=-6, c=7

 

Maximum = 4ac-b²

                        4a

 

Maximum = (4 x -8 x 7) - (-6)²

                          4(-8)

 

Maximum = (-224)- 36

                         32

 

Maximum= -260                         since (-224)- 36= -260

                       32

 

Maximum = -130 =   -65

                       16          8

 

Hence maximum value is -65/8

 

TRY THIS………………………………..

 

NECTA  2003 QN. 10c

 

Find the maximum value of the quadratic equation:3+30t-5t².

 

SIMPLIFY G1

 Simplify (6a)² - 30a². 

 

Solution

 

= (6a)² - 30a²    

 

= 6².a² - 30a²               Since (mn)² =m² . n²

 

= 36a² - 30a²   {since the square number of 6 is 36}

 

= 6a²

 

TRY THIS………………

 

Simplify (8m)² – 80m².