Scroll:Logarithms >> Find the value and solve the equation >> saq (4208)


Written Instructions:

For each Multiple Choice Question (MCQ), four options are given. One of them is the correct answer. Make your choice (1,2,3 or 4). Write your answers in the brackets provided..

For each Short Answer Question(SAQ) and Long Answer Question(LAQ), write your answers in the blanks provided.

Leave your answers in the simplest form or correct to two decimal places.



 

1)  

Simplify the following.

log2535 - log2510

(A)  log257 /2   (B)  log247/ 2    (C) log259/ 2   (D)  log246 /7 






Answer:_______________




2)  

Simplify the following.

log103 + log103

(A)  log108   (B)  log107    (C) log109   (D)  log10






Answer:_______________




3)  

 Find the value of following

 log (12) 8 = x


Answer:_______________




4)  

 Find the value of following

log7343 


Answer:_______________




5)  

 Find the value of following

log665


Answer:_______________




6)  

Solve the following equation. (use / )

x + 2log279 = 0


Answer:_______________




7)  

 Find the value of following

log3 (181)


Answer:_______________




8)  

Solve the following equation.

logx0.001 = -3


Answer:_______________




9)  

 Find the value of following

 Let log10 0.0001 = x


Answer:_______________




10)  

Simplify the following.

5log102 + 2log103 - 6log644

log10


Answer:_______________




 

1)  

Simplify the following.

log2535 - log2510

(A)  log257 /2   (B)  log247/ 2    (C) log259/ 2   (D)  log246 /7 





Answer: 2


SOLUTION 1 :

 log2535 - log2510

= log25( 3510)  

= log257/ 2



2)  

Simplify the following.

log103 + log103

(A)  log108   (B)  log107    (C) log109   (D)  log10





Answer: 4


SOLUTION 1 :

 log103 + log103

= 2log103 = log1032

= log109



3)  

 Find the value of following

 log (12) 8 = x

Answer: -3


SOLUTION 1 :

 log (12) 8 = x

⇒ ( 12) x = 8 = 23

= 2-x = 23 or  x = -3

 



4)  

 Find the value of following

log7343 

Answer: 3


SOLUTION 1 :

log7343 

= log77  = 3log77

 = 3(1) = 3

 



5)  

 Find the value of following

log665

Answer: 5


SOLUTION 1 :

log665  = 5



6)  

Solve the following equation. (use / )

x + 2log279 = 0

Answer: -43


SOLUTION 1 :

x + 2log279 = 0

x = - 2log279

⇒ 27x = 9-2

 (33)x   =  (32)-2     [ Change the base into 3 ]

⇒ 33x  =  3-4       [ Change the base into 3 ]

⇒ x  =   -43



7)  

 Find the value of following

log3 (181)

Answer: -4


SOLUTION 1 :

 log3  (181) =  log3 (13 )

= log31 - log334

 = 0= 4log33  = 0 - 4 = -4



8)  

Solve the following equation.

logx0.001 = -3

Answer: 10


SOLUTION 1 :

logx0.001 = -3

= x-3 = 0.001 = 10-3

x = 10.



9)  

 Find the value of following

 Let log10 0.0001 = x

Answer: -4


SOLUTION 1 :

 log10 0.0001 = x

= 10x = 0.0001 = 10-4

= x = -4



10)  

Simplify the following.

5log102 + 2log103 - 6log644

log10 Answer: 7225


SOLUTION 1 :

5log102 + 2log103 - 6log644

= 5log1025 + log1032  - log6446

= log1032 + log109 - log6464x64

= log1032x9 - 2log6464

= log10288 - 2log1010

= log10 288100

= log10 7225