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8-1

In 8-1 we learned about how an inverse has two answers. One is based off the trig. func. while the other is a positive or negative number. You have to follow the trig. func.'s value (ex. sin = y/r, so follow y) and you find the other quadrant where the number is positive or negative.

Steps:

Take the inverse of the positive number to find the quadrant 1 angle.

To get to:

Q2 make the angle negative and add 180°
Q3 Add 180°
Q4 make the angle negative and add 360°

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These steps allow you to move the angle to the other quadrants when told or specified to. Several examples were shown to us. Here is one example of this.

EX.

sin x=.6 for x

x=sin^-1(.6)

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we need to move to Q1 & Q2
(x=36.870° from the inverse)
.6*-1=-.6+180°

x=36.870°, 143.13°


another ex.

3cosΘ+9=7
3cosΘ=-2
cosΘ=-2/3

Θ=cos^-1(-2)

Θ=48.190°

now we need to find Q3 angle so we add 180°

Θ=48.190°, 288.190°

Overall I understood everything and know what to do for these examples and homework. This is Dylan so... :D