Developing computational capacity for students in teaching exponential functions, exponential functions and logarithmic functions in calculus 12 - 15

Student Activities

Content

Question: State

how to calculate, solve,...

HD7: Similar to HD 5

HD 8:

Method 1: Solve Method 2: Calculator

x 2  2 x  3

Enter 2  8 x

Then CALC the input results. Get result A

HD 9 : Similar to HD 8

7. Let log a b  3, log a c   2 . Calculate log a x

a) x = a 3 b 2 c

b) x = a 4 3 b

c 3

x 2  2 x  3

8. Find the solution set 2  8 x .

A. _ S   1 ;3  . B. S    1;3  .

C. S    3;1  . D. S    3  .

9. Find the solution set of the equation

l og  x  1   log 1  x  1   ​​1.

2

2

A.   3  13   . B.  3  .

  2  

 

C.  2  5;2  5  . D .  2  5  .

10. Solution set of inequalities:

2019 x  3 x  1  2019 x  2  x 2  3 x  x  3  0

2

A.    ;0  B . 

C .  3  D.  3 ;  

11. Mr. Y saves 75 million in the bank for a term of 3 months and an interest rate of 0.59%/month. If Mr. A does not withdraw interest at all terms, then after 3 years, Mr. A will receive the amount of

A. 92576000 B. 80486000

Student Activities

Content

HD 10 : In the solution region, we CALC some values ​​that satisfy answer C

H D 11 : S n  A .  1  r 

n

Interest rate 3.0.59%=1.77%.

After 3 years (12 quarters), the amount collected, both principal and interest, is: 92576000

C. 92690000 D. 90930000

Activity 3. Discover, evaluate, explore and solve problems

Question: Read

HD 12:

12. A person regularly deposits an amount of money T in the bank every month in the form of compound interest at an interest rate of 0.6% per month. Knowing that after 15 months that person will have 10 million VND. Which of the following numbers is the amount T closest to?

A. 535,000 B. 635,000

C. 613,000 D. 643,000

Answer

1 0 .0 0 0 .0 0 0  T   1  0, 6 %  1 5  1  .  1  0, 6 %   T  6 3 5 .0 0 0

0 , 6 %  

13. Le's mother borrowed 50 million VND from the bank in installments with an interest rate of 1.15%/month for 2 years.

subject, division

After n months  n  N * 

search, search

To be :

solution.

S  A   1  r  n  1   1  r 

n r  

Student Activities

Content

HD 13:

The way to calculate the remaining amount after n months is exactly the same as the formula for calculating monthly bank deposits and withdrawals:

How much does Ms. Nam have to pay each month?

A. 1361313 VND B.136132 VND C. 136131 VND D. 1361312 VND Answer:

 1  r  n  1

S  A  1  r  n  X .

n r

5.10 7 .  1, 0115  48 .0, 0115

X   1 , 0115  4 8  1  1361312, 807

14. How many positive integer values ​​of the parameter are there for the equation

Does 16 x  2.12 x  ( m  2)9 x  0 have a positive root?

A. 1. B . 2 . C. 4 . D. 3 .

Answer:

Return the equation to:

2.9 x  2.12 x  16 x

m 

9x _

- HD: use mode 7

- Click MODE 7 to enter into the computer

2.9 x  2.12 x  16 x

f ( x ) 

9x _

Select Start -9 end 9 step 1

We can see that f(x) is positive in the solution region (0.2; 2.9).

Student Activities

Content

HD 14:

Method 1 : Who solves?

- Students: divide into 2 sides

.16 x . or 9x

- Students solve and find 2 values ​​of m. The result is Method 2: Explore

- Teacher: If m = f(x) how do you plan to use the calculator?

- Students: can find the hemorrhoidal value range of f(x)

- Teacher: What is the most effective way to find the value domain? HD 15:

Method 1 : Who solves?

- Students divide the two sides

4 x or 9 x

- Students solve for x and get 2 solutions: x = 0;

x  log  2 

3  9 

2  

The result is C Method 2: Explore

So m = 1 and m = 2. Answer B.

15. Number of solutions of the equation

2.4 x  9 x  1  11.6 x

A. 0 B. 1 C . 2 D. 3

Prize

Method 2: Enter MODE 7 into the computer

f ( x )  2.4 x  9 x  1  11.6 x

Select Start -9 end 9 step 1 Get 2 positive f(x) regions, 1 negative f(x) region. Conclusion: There are 2 times f(x) changes sign. The result f(x) = 0 has 2 solutions. Answer C

Activity 4. Consolidation