To prove a trigonometric identity,
-Simplify one or both sides of an equation so that they are equal.
-When solving DO NOT cross over the equal sign.
-Know the fundamental Pythagorean identities.

There are many different approaches one can take when solving such problems, to use the shortest method possible keep these things in mind:
1. Try to stay on one side, and start with the side that has addition or subtraction.
2. Simplify terms as much as possible. Look out for:

fractions or like terms that can be combined

anything that can be factored in order to simply the expression (difference of two terms or perfect square trinomials.

denominators that can be mulitipied by the conjugate

Algebreic expressions that can be distributed, squared or multiplied.

3. Change trig functions to Sin and Cos.

Some Examples Of Proofs:

Proof: cscx = cotx/cosx

Step 1: Equation becomes: cscx = cosx/cosxsinx
*The cot(x) was changed to cos(x) over sin(x) Step 2: Equation becomes: cscx = 1/sinx
*Cos(x) over Cos(x) cancle and change to just one. Step 3: Equation becomes: cscx = cscx
*One over Sin(x) is the same as Csc(x)

ALWAYS write out the entire equation for each step of the process

Learn How To Do ItTo prove a trigonometric identity,-Simplify one or both sides of an equation so that they are equal.

-When solving DO NOT cross over the equal sign.

-Know the fundamental Pythagorean identities.

There are many different approaches one can take when solving such problems, to use the shortest method possible keep these things in mind:1. Try to stay on one side, and start with the side that has addition or subtraction.

2. Simplify terms as much as possible. Look out for:

- fractions or like terms that can be combined
- anything that can be factored in order to simply the expression (difference of two terms or perfect square trinomials.
- denominators that can be mulitipied by the conjugate
- Algebreic expressions that can be distributed, squared or multiplied.

3. Change trig functions to Sin and Cos.Some Examples Of Proofs:Proof:cscx = cotx/cosxStep 1:Equation becomes: cscx = cosx/cosxsinx*The cot(x) was changed to cos(x) over sin(x)

Step 2:Equation becomes: cscx = 1/sinx*Cos(x) over Cos(x) cancle and change to just one.

Step 3:Equation becomes: cscx = cscx*One over Sin(x) is the same as Csc(x)

ALWAYS write out the entire equation for each step of the processProving Trigonometric IdentitiesLet's PracticeLet's ReviewThe video below is a different way to prove a trigonometric identity, but it still works. It's an interesting way to look at proving identities!

andhttp://www.youtube.com/watch?v=18ZQd12Vq28

Use this link for more practice: http://www.algebralab.org/practice/practice.aspx?file=Trigonometry_BasicTrigIdentities.xml