# Write an exponential function for the graph where is x

In Excel, the Power function returns the result of a number raised to a given power. The syntax for the Power function is: Power number, powernumber is a base number, power is the exponent used to raise the base number to. The student does not understand the basic form of an exponential function. Examples of Student Work at this Level The student attempts to write a linear function or an exponential expression.

Questions Eliciting Thinking What is an exponential function? What does the equation of an exponential function look like? How would you describe this graph?

Provide opportunities for the student to explore and investigate exponential functions given in context. Include examples of both growth and decay. Explain the significance of points whose coordinates are of the form 0, x and 1, x and demonstrate how these points can be used to write the equation.

Encourage the student to relate features of the graph to the parameters in the equation. Also, provide opportunities for the student to write exponential functions given a verbal description, a graph, or a table of values.

If the student wrote a linear function, ask the student to graph the function and compare it to the given graph. Discuss with the student differences in the rates of increase of the two functions and relate these differences to the forms of the equations.

If needed, review function notation and guide the student to use function notation when writing functions. Provide frequent opportunities to use function notation, so the student can become familiar and comfortable with its use. Moving Forward The student is unable to correctly calculate one or both parameters.

Examples of Student Work at this Level The student correctly identifies the initial amount but: Calculates the slope of the line containing 0, 0. Is unable to solve the equation to find the growth factor.

Questions Eliciting Thinking What does the value you calculated,tell you about this graph? What are the two important parameters of an exponential function? Can you describe them in words?

## Key Questions

Which one did you find? Instructional Implications Explain the significance of points whose coordinates are of the form 0, x and 1, x and demonstrate how these points can be used to write the equation. Provide additional examples of the graphs of exponential functions and model writing the equation using well-chosen points on a graph.

Almost There The student makes a minor error in calculating a parameter or writing the function. Examples of Student Work at this Level The student:Write an exponential function y=ab^x for a graph that includes (-4,72) and (-2,18) Ask for details ; Follow Y=9/2*^x.

Download gif. 0 votes 0 votes Rate! Rate! Thanks. 1. Comments; Report What is the period of the function y= cos(x/2) A. 2pi B. pi/4 C. pi D. 4pi Mathematics; 15 points. Notice that b(x), c(x), and d(x) in Example are not exponential functions. Example (Understanding Exponential Growth) Suppose that you place a bacterium in a jar. Graphing the exponential function and natural log function, we can see that they are inverses of each other. Let's graph the function f(x) = log(x+2) of base 4. We can use the definition of logs to rewrite this in exponential form. Domain and Range of Exponential and Logarithmic Functions Recall that the domain of a function is the set of input or x -values for which the function is defined, while the range is the set of all the output or y -values that the function takes.

More Exponential Function Tables and Word Problems. Directions for 1 – 4: Write the equation for the table. Write a function formula relating the variables x = the stage of the calling process and y = the number of bacteria present at that stage.

c. Graph the points on the grid. d. Using the equation y = ab x, substitute both of your given points into that equation.

How to do exponential calculation to a range of cells in Excel?