The diagram shows part of the graph of the function $y = p \, ext{cos} \, qx + r$ - Scottish Highers Maths - Question 4 - 2015
Question 4
The diagram shows part of the graph of the function $y = p \, ext{cos} \, qx + r$.
Write down the values of $p$, $q$ and $r$.
Worked Solution & Example Answer:The diagram shows part of the graph of the function $y = p \, ext{cos} \, qx + r$ - Scottish Highers Maths - Question 4 - 2015
Step 1
state the value of $p$
96%
114 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
From the graph, we observe that the amplitude of the cosine function is 3. Therefore, the value of p is equal to 3.
Step 2
state the value of $q$
99%
104 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The graph indicates that one complete cycle of the cosine function occurs between 0 and rac{eta}{2} which is a range of rac{eta}{2}. Thus, the value of q is 4.
Step 3
state the value of $r$
96%
101 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The vertical shift of the cosine function can be determined from the graph where the midline is at y=1. Therefore, the value of r is equal to 1.
Join the Scottish Highers students using SimpleStudy...
