Pre-calculus help.

Pre-College Issues High School Life
1

<p><a href="http://catcode.com/trig/trig09.html%5B/url%5D"&gt;http://catcode.com/trig/trig09.html&lt;/a&gt;&lt;/p>

<p>On the frequency and amplitude page, describe what happens to the frequency and amplitude when you input the functions at the bottom of the page:
2 sin(A)
sin(2A)
sin(0.5A)
2 sin(0.5A)
0.5 sin(2A)</p>

<p>I'm starting trignometry unit soon, so this is just a preview.
I know how to put in the functions, and I also know what frequency and amplitude mean.</p>

<p>The only trouble that I'm having with this problem is that when it asks me to describe the frequency and amplitude when I put in the functions.
I have no idea how to describe them. How do I determine the speed of the wave and min. and max. values of each function?</p>

2

<p>First plot sin(A) and look at it. The greatest positive value is 1 and the most negative value is -1, and it takes four of the horizontal divisions to complete the cycle. Now plot 2sin(A). You will see that the amplitude has increased to +2 and -2, and the cycle still takes four horizontal divisions to repeat. Therefore the amplitude has increased by a factor of 2 and the frequency is unchanged.</p>

<p>Comparing sin(2A) with sin(A), you should see that the amplitude is unchanged and the pattern repeats twice in four horizontal divisions. Therefore the frequency has doubled.</p>

<p>Describe the others in similar manner.</p>