How do I factorise this radian equation?

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Factorise:

2sinx cosx - 4sin^3x cosx

I don't want just a simple explanation with an answer, I need a full explanation of every mathematical step.
 
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2 * S * C - 4 * S * S * S * C

cant you see the common factors in each term?

we can't help you if you don't show any work.
 
is this a repeat post of the same problem?

This was previously posted in another thread!
 
Last edited:
Olly_price said:
Factorise:

2sinx cosx - 4sin^3x cosx
How's your algebra skills? If you can factorize this algebraic expression:
2xy - 4x3y
... then you should be able to factorize the original problem in a similar way.

Olly_price said:
I don't want just a simple explanation with an answer, I need a full explanation of every mathematical step.
Sorry, no can do. If this is homework, then giving solutions would be against the forum rules.
 
You simply MUST provide some intial steps on your own (you DO have that, right?)
THEN, we can help you along with some more!

While your expression can most elegantly be expressed strictly in terms of a single sine function, with amplitude one half, you need to show some willingness to get there at least some part of the way.
 
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Your steps are:

1. Call sin(x)=a, cos(x)=b and rewrite the expression.
2. Factor the expression with respect to a and b. (You know how to do that, right?)
3. Substitute the trigonometric functions back.
4. Write down the trigonometric identities you know.
5. If you still can't see the solution, please reply (show some working.)
 
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