Help with trigonometry please sin...

[JKearnsl]

sin⁴(4x) + cos²x = 2sin(4x)cos⁴x

I can’t solve it
Help with trigonometry please

 

[Deleted member 4993]

sin⁴(4x) + cos²x = 2sin(4x)cos⁴x

I can’t solve it
Help with trigonometry please

Hint:

sin⁴(a) = sin²(a) * sin²(a) ....... and

sin²(a) =1 - cos²(a)

Please show us what you have tried and exactly where you are stuck.

Please follow the rules of posting in this forum, as enunciated at:

https://www.freemathhelp.com/forum/threads/read-before-posting.109846/#post-486520

Please share your work/thoughts about this assignment.

 

[JKearnsl]

Hint:

sin⁴(a) = sin²(a) * sin²(a) ....... and

sin²(a) =1 - cos²(a)

Please show us what you have tried and exactly where you are stuck.

Please follow the rules of posting in this forum, as enunciated at:

https://www.freemathhelp.com/forum/threads/read-before-posting.109846/#post-486520

Please share your work/thoughts about this assignment.

Your answer pleased me, but I’ve been trying to solve this for several hours, but it’s not working out for me. Maybe I'm trying to find some formula in this equation, I don’t know.

 

[JKearnsl]

Hint:

sin⁴(a) = sin²(a) * sin²(a) ....... and

sin²(a) =1 - cos²(a)

Please show us what you have tried and exactly where you are stuck.

Please follow the rules of posting in this forum, as enunciated at:

https://www.freemathhelp.com/forum/threads/read-before-posting.109846/#post-486520

Please share your work/thoughts about this assignment.

I'm at a dead end

 

[pka]

The graph is this link, look at this graph.
It shows that the given is not an identity.
Are you rather to solve the equation for values of \(x~?\).
If so look here

 

[yoscar04]

The graph is this link, look at this graph.
It shows that the given is not an identity.
Are you rather to solve the equation for values of \(x~?\).
If so look here

Nice, but even if he finds difficult to plot it, it can be seen that x=0 doesn't fulfill the equality, so it is not a trigonometric identity but an equation. Actually I tried writing sin(4x) in terms of x and it gets a bit messy.

 

[Deleted member 4993]

Nice, but even if he finds difficult to plot it, it can be seen that x=0 doesn't fulfill the equality, so it is not a trigonometric identity but an equation. Actually I tried writing sin(4x) in terms of x and it gets a bit messy.

A bit messy !! - huge understatement!

You can also disprove this to be "identity" by putting x = π/4.

I think only way this can be solved is through is "estimation".

 

[yoscar04]

Part of the solutions given by Wolfram (courtesy of pka) looks very neat:

 

[yoscar04]

Part of the solutions given by Wolfram (courtesy of pka) looks very neat: View attachment 20423

How come x=[MATH]\pi[/MATH]/4 is a solution?

 

[Cubist]

How come x=[MATH]\pi[/MATH]/4 is a solution?

@pka made a mis-type of cos(2x) instead of cos^2(x)

Here's a link with the typo corrected

 

[yoscar04]

sin⁴(4x) + cos²x = 2sin(4x)cos⁴x

I can’t solve it
Help with trigonometry please

Is this a textbook problem?

 

[Steven G]

@pka made a mis-type of cos(2x) instead of cos^2(x)

Here's a link with the typo corrected

Is that supposed to be any better?

 

[Steven G]

Is this a textbook problem?

I bet you that the plus sign should not be there.

 

[JKearnsl]

Is this a textbook problem?

idk. I found this on the Internet and I want to decide!
But I can’t do it

 

[JKearnsl]

I bet you that the plus sign should not be there.

Is it possible to simplify the expression?

 

[Dr.Peterson]

idk. I found this on the Internet and I want to decide!
But I can’t do it

Please provide a link to the original you found, so we can verify whether it is copied correctly, and whether the context tells us anything about how to correct the problem. As it stands, the problem appears to be simply wrong.

 

[JKearnsl]

Please provide a link to the original you found, so we can verify whether it is copied correctly, and whether the context tells us anything about how to correct the problem. As it stands, the problem appears to be simply wrong.

https://znanija.com/task/3180151