FUNCTIONS D3

Given that F(x) = 3x  +  11. Find F(-2) – 2F(5)

 

Solution

 

CASE 1: We find F(-2)

 

 

F(x) = 3x  +  11

 

F(-2) = 3(-2)  +  11

 

F(-2) = -6  +  11

 

F(-2) = 5

 

 

Hence  F(-2) = 5

 

 

 

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CASE 2: We find F(5)

 

 

 

F(x) = 3x  +  11

 

F(5) = 3(5)  +  11

 

F(5) = 15  +  11

 

F(5) = 26

 

 

Hence  F(5) = 26

 

 

2F(5) = 2(26) = 52

 

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CASE 3: We find F(-2) – 2F(5)

 

 

= F(-2) – 2F(5)

= 5 – 52

= -47

 

 

TRY THIS………………..

 

 

 

Given that F(x) = 12x  +  78. Find F(-20) – 2F(10)

FUNCTIONS D2

 

LOGARITHMS D1

 

Change the following into Logarithmic form.

i)  4² = 16

ii)  5³ = 125

iii)  3⁰ = 1

Solution

 

 

4² = 16 ⇔ log₄ 16 = 2

5³ = 125 ⇔ log₅ 125 = 3

3⁰ = 1 ⇔ log₃ 1 = 0

TRY THIS………………….

Change the following into Logarithmic form.

i)  7² = 49

ii)  3⁴ = 81

iii)  8⁰ = 1 

FUNCTIONS D1

 

Given that F(x) = 7x  +  11. Find F(-2)

 

Solution

 

F(x) = 7x  +  11

 

F(-2) = 7(-2)  +  11

 

F(-2) = -14  +  11

 

F(-2) = -3

 

 

Hence  F(-2) = -3

 

 

TRY THIS………………..

 

 

Given that F(x) = 16x  +  23. Find F(-3)

CAPACITY D1

 

Change 32.6 liters of water into centiliters

 

Solution

 

1L  =  100cl

32.6L = ?

___________________________  

 

 = 32.6 x  100

           1

 

= 32.6 x 100

 

= 3260cl. Answer

 

 

TRY THIS...................................

 

 

Change 154.3 liters of milk into centiliters