If variable y ranges from 0 to 25000 mm and you define Y=1000y in metres, find the range of Y.
[2]
Question 2
Skill question
An experiment yields the best-fit line
ln(P)=−0.2t+3.5
Express P as an exponential decay model in the form P=Aert, where A and r are constants.
[4]
Question 3
Skill question
Convert the model y=5erx into a linear model involving log10(y) and x.
[3]
Question 4
Skill question
Comparison of linear regression on transformed data with exponential models.
A best‐fit line for ln(y) versus x is given by
ln(y)=0.693+0.05x.
Determine the parameters A and r of the equivalent exponential model y=Aerx. [3 marks]
[3]
Question 5
Skill question
Express the exponential model y=10e2x as a linear relationship between ln(y) and x.
[2]
Question 6
Skill question
Convert the masses 50 g, 1500 g and 25000 g to kilograms. Define M=1000m where m is in grams. What are the values of M?
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Question 7
Skill question
The exponential model is y=5erx.
Show that plotting ln(y) versus x yields the straight-line equation ln(y)=ln(5)+rx.
[3]
Question 8
Skill question
Express the model y=12e−0.5x in the form ln(y)=mx+c and identify m and c.
[3]
Question 9
Skill question
A process takes times t=1800s, 5400s and 9000s. A scaled variable T is defined by T=3600t, where T is measured in hours. Calculate the values of T.
[2]
Question 10
Skill question
The question requires converting a linear equation in a log-linear coordinate system (base 10) into an exponential model with base e.
Given the straight-line fit log10(y)=1.301+0.02x, find the equivalent exponential model y=Aerx.
[4]
Question 11
Skill question
A company’s monthly revenue ranges from $200,000 to $1,500,000. If R=106revenue represents the revenue in millions of dollars, find the minimum and maximum values of R.
[3]
Question 12
Skill question
Given the exponential decay model N=40e−0.5t, find the half‐life T1/2 of N.