Pre-Calculus 1/26

Today we learned how to find the sin(x), and what that looks like on a graph.

We found the (sin) of five different points using our Unit Circles:

We then used those points to make a graph:

We then found the domain, range, and period for the graph:

(the Period is to what (x) plot the data goes)

Domain: All Real Numbers

Range: [-1,1]

Period: 2(pi)

We also learned how to graph 2sin(x):

Domain: All Real Numbers

Range: [-2,2]

Period: 2(pi)

As you can see, the range became bigger. This increases the graph's AMPLITUDE.












Edited by Mr. Corn....

Let's also look at a graph where the variable is multiplied by a constant....

y = sin(2x)



The red graph represents the graph of sin(2x). It's period is double of the base graph of sin(x) in blue.

The period of the red graph is pi

The period of the blue graph is 2pi






Helpful hints:

1. To find amplitude, take the absolute value of the coefficient in front of sine. For example, the amplitude of y = -3sin(x) is 3.

2. To find the period of y = sin(bx), calculate 2pi divided by b.

3. When drawing these graphs by hand, ALWAYS list your x values on the x axis. Examples of this can be found on Mr. Corn website here.