(Trig) Rewriting using power-reducing formula?

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SUMMARY

The discussion focuses on rewriting the expression sin4x tan4x in terms of the first power of cosine using power-reducing formulas. The key equations utilized include sin2x = (1 - cos x)/2 and tan2x = (1 - cos x)/(1 + cos x). The solution involves transforming sin4x and tan4x to ultimately express the equation in terms of cosine, specifically addressing the challenges of dealing with higher powers and resulting cubic functions.

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Homework Statement


Rewrite sin^4 xtan^4 x in terms of the 1st power of the cosine.


Homework Equations


sin^2 x=(1-cosx)/2
tan^2 x=(1-cosx)/(1+cosx)

The Attempt at a Solution


Imoxe.jpg


For this problem, I tried to rewrite tan^2 x as (sin^2 x/cos^2 x)
But then I ended up with a...cubic function, which made the problem even more complicated. What am I doing wrong here?
 
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The problem you posted was sin4(x) tan4(x). -- both with the power, 4.

Your answer still has cos3 & cos2 .

sin4(x)

= (1-cos2(x))sin2(x)

= sin2(x) - cos2(x)sin2(x)

= (1 - cos(2x))/2 - sin2(2x)/4

...
 

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