Math Problem Statement

Find a formula for the exponential function, given points (10, 320) and (30, 20). Round a to the nearest integer and b to three decimal places.

Solution

To solve this, we're given an exponential function y=abxy = ab^x and two points from the graph: (10, 320) and (30, 20). We need to determine the values of aa and bb, then round aa to the nearest integer and bb to three decimal places.

Step-by-step solution:

  1. Start with the general exponential form: y=abxy = ab^x Given two points: (x1,y1)=(10,320),(x2,y2)=(30,20)(x_1, y_1) = (10, 320), \quad (x_2, y_2) = (30, 20) Substituting these into the equation will give us a system of two equations.

  2. Substitute the first point (10, 320): 320=ab10320 = ab^{10}

  3. Substitute the second point (30, 20): 20=ab3020 = ab^{30}

  4. Solve the system of equations: Divide the second equation by the first to eliminate aa: 20320=ab30ab10\frac{20}{320} = \frac{ab^{30}}{ab^{10}} Simplify: 116=b20\frac{1}{16} = b^{20} Take the 20th root of both sides to solve for bb: b=(116)120=16120b = \left( \frac{1}{16} \right)^{\frac{1}{20}} = 16^{-\frac{1}{20}}

    Now, we calculate bb.

  5. Find aa: Once bb is determined, substitute it back into one of the original equations (e.g., 320=ab10320 = ab^{10}) to solve for aa.

Let me now compute these values.The formula for the exponential function is:

y=12800.871xy = 1280 \cdot 0.871^x

Where:

  • a=1280a = 1280 (rounded to the nearest integer)
  • b=0.871b = 0.871 (rounded to three decimal places)

Do you have any questions or would you like further details?

Here are 5 related questions:

  1. How do exponential functions behave for negative values of xx?
  2. Can exponential functions ever result in zero? Why or why not?
  3. How can you determine the rate of decay from an exponential function?
  4. What is the significance of the base bb in the context of growth and decay?
  5. How do logarithms relate to solving exponential equations?

Tip:

When working with exponential functions, the base bb (if 0<b<10 < b < 1) represents decay, and if b>1b > 1, it represents growth.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Exponential Functions
Algebra

Formulas

y = ab^x

Theorems

Laws of Exponents
System of Equations

Suitable Grade Level

Grades 9-12