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Guest123

Guest

Help with functions

There are two situations I want to express as a function and make a graph.
The assignment is about viruses that spread.
Country A) Here, the number of infected increases with the number of days in the epidemic multiplied by itself.
Country B) Here we see that the number of infected people doubles every day.

If someone can help, thank you

KerimF

Member

From: Aleppo-Syria

Registered: 2018-08-10

Posts: 256

Re: Help with functions

I wonder what the number of infected people (y) is supposed to be on the first day (x=1).
Is it y=1 for x=1?

Last edited by KerimF (2024-03-05 09:29:50)

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amnkb

Member

Registered: 2023-09-19

Posts: 253

Re: Help with functions

Im not sure what you mean for A.

For B do doubles:
x=0,y=0
x=1,y=2
x=2,y=4
That's 3 pts
You can find strait line equation

mathxyz

Member

From: Brooklyn, NY

Registered: 2024-02-24

Posts: 1,053

Re: Help with functions

Part A of this question is poorly worded. I  trying to make sense of the directions.

Bob

Administrator

Registered: 2010-06-20

Posts: 10,640

Re: Help with functions

hi Guest123

Welcome to the forum.

Country A) Here, the number of infected increases with the number of days in the epidemic multiplied by itself.

I'll assume that the number at the start is A, and use d for the number of days.

Multiply by itself: I think this means d squared so we have the formula

This graph starts at d = 1.  If you want it to start at day 0 then change the formula to

The graph for this is a quadratic. 

Country B) Here we see that the number of infected people doubles every day.

At the start I'll again say A people infected on day 0. Next day (d=1)  2A. Next day (d=2) 4A. Next day (d=3) 8A.

That results in the formula:

The graph for this is exponential.

https://www.mathsisfun.com/data/function-grapher.php

Bob

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