The notes from sections 8-1 and 8-2.

In section 8-1 we are solving for (theta), to solve for (theta) you have to get the trig function by itself and then take the inverse of it.

- an inverse has two answers with some exceptions, find some exceptions, findwhere the angle is based on the trig function and if the number is positive or negative.

Steps:

1. take the inerse of the positive number to find the Q1 angle to get this

Q2: make negative degrees and add 180 degrees.

Q3: Add 180 degrees.

Q4: Make negative degrees and add 360 degrees.

Ex 1:

Solve sin x= -6 for x

x= sin-1 (.6)

x= 36.870, 143.130 degrees

8.2

In this section you are graphing the period changes of sine and cosine.

- y= Asin Bx or y= A cos Bx

- absolute value of {A} = amplitude

-2(pie)= Period

Steps:

Take all 5 points (0, (pi)/2, (pi), 3(pi)/2, 2(pi))

- divide by B

-Sketch the graph

Ex

y=4sin3x

amp: l4l = 4
Pi/6period: 2pi/3 =2pi/3

Now by dividing 0, pi/2, pi, 3pi/2, & 2pi by 3, you get these 5 points.
0/3= 0
pi/2/3= pi/6
pi/3= pi/3
3pi/2/3= pi/2
2pi/3=2pi/3