The Mind-Boggling World of Exponential Functions!
- Terry Presswood
- Oct 25, 2023
- 3 min read
My first blog post on Wix! To discover they do not carry over formatting if you originate in another compiler! Then, to discover there is no such thing as superscript or subscript here. So I attached the formatted document at the bottom. It should be easier and friendlier to look at.
Welcome, high school math enthusiasts! Get ready to dive deep into the captivating realm of exponential functions, where growth and change take center stage. Buckle up as we explore this moderately advanced topic, complete with real-life examples and problem-solving adventures. Let's unlock the secrets of exponential functions together!
Exponential functions are like superheroes of mathematics. They depict situations where a quantity changes at a constant multiplicative rate. In simpler terms, things blow up or shrink down in a predictable and exciting way. So, let's embark on our adventure!
Imagine you have invested $1,000 in a savings account that offers an annual interest rate of 10%. Each year, your money grows by 10%. With exponential growth, you can predict how much money you'll have in the account after a specific number of years.
To determine the future value of your investment, we can use the formula:

Where:
A = Future value of the investment
P = Initial principal (in our case, $1,000)
r = Interest rate (in decimal form; 10% becomes 0.1)
t = Number of years
Let's calculate the future value after 5 years using this formula:

Opening our math toolbox, we solve step by step:

[A = 1000(1.1)^5 = 1000(1.61051)]
[A ≈ $1,610.51]
Amazing, right? Your $1,000 investment grew to $1,610.51 in just 5 years, thanks to the power of exponential growth!
Now, let's explore real-life scenarios where exponential functions come into play:
Example 1: Population Growth 🌍
Human populations follow exponential growth patterns. Imagine a town with a population of 1,000 people and an annual growth rate of 3%. Using the formula, we can predict the population after 10 years:

Applying our mathematical prowess:

[P ≈ 1000(1.34392)]
[P ≈ 1,343.92]
In just 10 years, the town's population is estimated to be around 1,343 people. Isn't that fascinating?
Example 2: Compound Interest 💰
When you borrow money or take out a loan, you'll often encounter compound interest. Let's say you've borrowed $5,000 at an annual interest rate of 6%. After 3 years, you want to know how much you need to repay. We can use our trusty formula once again:

Solving the equation:

[A ≈ 5000(1.191016)]
[A ≈ $5,955.08]

After 3 years, you would need to repay approximately $5,955.08. Compound interest can quickly add up, so it's essential to understand its impact.
Now, it's time to test your newfound knowledge with some practice questions. Sharpen those pencils and put your skills to the test!
1. What would be the future value of $1,500 invested for 8 years at an annual interest rate of 8%?
2. If a population of rabbits grows at a rate of 20% per year and begins with an initial population of 100, how many rabbits will there be after 6 years?
3. If you borrow $10,000 at an annual interest rate of 4% with monthly compounding, how much would you need to repay after 5 years?
Solve these problems with confidence, and when you're ready, let's check your answers together!
Fantastic work, my math-magicians! You've tackled exponential functions head-on, delved into real-world examples, and solved problems like true math superheroes. Never stop exploring the endless wonders of mathematics, as it unveils the mysteries of our world with its formulas and patterns.
Remember, math is not just about numbers; it's about building problem-solving skills, critical thinking, and embracing the joy of discovery. So, embrace the challenge, embrace exponential growth, and let the magic unfold!

Comments