This presentation is the property of its rightful owner.
1 / 12

# 11-2 Exponential Functions PowerPoint PPT Presentation

11-2 Exponential Functions. Power Function – a function with base x and any real number as the exponent (ex: y= x 4 ) Exponential Function- function with a positive base and a variable as the exponent (ex: y = 3 x ). Exponential Regression.

11-2 Exponential Functions

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

## 11-2 Exponential Functions

Power Function – a function with base x and any real number as the exponent (ex: y=x4)

Exponential Function- function with a positive base and a variable as the exponent (ex: y = 3x)

### Exponential Regression

You can find the equation of an exponential function just like we did for linear.

• Type in data

• Turn on Stat Plot-Zoom 9

• Stat-Calc-0ExpReg

### Find the equation for..

• A cup of coffee is 95°C in a room that is 20°C. The cooling for this cup can be modeled by the equation y=75(.875)t where y is the temperature and t is the time in minutes. Find the temperature after 15 minutes.

Exponential Functiony = a • rt

a = original amount, r = rate t= time

Rate can be several things….

(1 ± %) for growth or decay

(2) For “double”

(1/2) for half life

What is the original amount and how much is each item increasing/decreasing?

• Y=4 (.90)x

• Y=200 (.75)x

• Y=5(1.10)x

• Y=½ (1.50)t

3) Suppose two mice live in a barn. If the number of mice quadruples every 3 months, how many mice will be in the barn in after 2 years?

4) How much will a car be worth in 5 years if you bought it for \$20,000 and it depreciates 16% each year?

5) John gets a 2% pay raise every year. If right now he makes \$8.00 an hour, how much will he make in 2020?

When kerosene is purified to make jet fuel, pollutants are removed. Suppose a filter is fitted in a pipe so that 15% of impurities are removed for every foot that the kerosene travels.

Write an exponential function to model the situation

About what percent of impurities will remain after the kerosene travels 12 feet.

Will the impurities ever be complete removed? Why/Why not?

### Compound interest

A

A- total amount

P-principal (original amount)

R-interest rate

N-number of time compounded each year

• Find the total amount of money in an account at a rate of 5% compounded daily if Mrs. K invest \$2000 for 7 years.

• Find the amount of interest charged on a credit card if left unpaid for 3 years if the original amount was \$1000 compounded 12% monthly.