Chapter 4.5(Prove Trigonometry Identities)

Pythagorean Identity

Quotient Identities


Reciprocal Identities

The last part of the chapter, proving trigonometry identities. above is some new formulas that quite useful for you to use as you are working on proving.

Chapter 4.4 ( Compound Angle Formulas )

The following are important trigonometric relationships:

sin(A + B) = sinAcosB + cosAsinB
cos(A + B) = cosAcosB - sinAsinB
tan(A + B) =   tanA + tanB
                  1 - tanAtanB

sin(A - B) = sinAcosB - cosAsinB
cos(A - B) = cosAcosB + sinAsinB
tan(A - B) =   tanA - tanB 
                    1 + tanAtanB




Memorize all the formulas above and twist it around (depends on your creativity and the requirement from questions).

Chapter 4.3 (Equivalent Trigonometric Expressions)

we learn this chapter through blended learning, i understand the chapter through my own confusing method, however i could not put it in words to explain. Therefore, i search online and found some really good videos and blog on explaining this chapter in detail.

Here's some of my course mate's blog, i strongly advice you take a look on their blog as you may find some really good explanation on the chapter.

http://advfunctfreaks.blogspot.com/

http://letscount-af.blogspot.com/

Chapter 4.2 (Trigonometric Ratios & Special Angles)

In this unit, our main focus is on trigonometric ratios and special angles.

There are 6 trigonometric ratios for us to memorize - tangent (tan), sine (sin), cosine (cos), cosecant (csc), secant (sec) & cotangent (cot).

While the special angles are 30˚, 45˚ and 60˚.

Csc, sec & cot are the reciprocal of sin, cos and tan respectively.

  

this is a picture of a special angle ( sixty degree and thirty degree)

this is another picture of a special angle ( forty degree)

however i found a table in my friend's blog which i think its pretty useful.

It really helps me a lot in understanding the triangle. 

In this chapter, we need to use the CAST rule to calculate the exact value for the triangle. 

What is CAST rule ? 

Well, i found a video about the CAST rule, i hope it helps

Feel free to comment if you do not understand, i will try to explain it in detail :)

Chapter 4.1 (Radian Measure)

In this Unit We are going to deal with π and radian.


Radian measure of angle θ is defined as the length of arc, a, that subtends the angle divided by the radius of the circle, r.


Here's some simple method on how to count radian and degree.