Help verifying a trig identity?

In summary, the conversation is about verifying the identity (sin^3(x)-cos^3(x))/(sinx-cosx) = 1+(sinx*cosx). The person is following a similar method as a post they found, but they are getting a different result and need help. The suggested solution involves using the identity for the difference of cubes and using the Pythagorean identity for sin and cos.
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multiply the right hand side by one in the form
[tex]\frac{\sin(x)-\cos(x)}{\sin(x)-\cos(x)}[/tex]
and use
[tex]\cos^2(x)+\sin^2(x)=1[/tex]
 

1. What is a trig identity?

A trigonometric identity is a mathematical equation that is true for all values of the variables involved. In other words, it is a statement that is always true, regardless of the specific values of the angles involved.

2. Why is it important to verify trig identities?

Verifying trig identities is important because it allows us to check the validity of a mathematical equation and ensure that it is true for all possible values. This is especially useful in higher level mathematics and engineering where trigonometry is heavily used.

3. What are some common trig identities?

Some common trig identities include the Pythagorean identities, double angle identities, half angle identities, and sum and difference identities. These identities can be used to simplify trigonometric expressions and solve equations.

4. How do I verify a trig identity?

To verify a trig identity, you must manipulate the given equation using algebraic and trigonometric properties until both sides of the equation are equivalent. This involves using known identities and trigonometric formulas to rewrite the expression in a different form.

5. What are some tips for verifying trig identities?

Some tips for verifying trig identities include starting with the more complex side of the equation, using common identities to rewrite expressions, and being familiar with trigonometric properties and formulas. It is also helpful to practice and check your work by substituting in different values for the variables.

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