- #1

- 31

- 0

How do you find the solution tan(x)=sin(2x)?

- Thread starter princiebebe57
- Start date

- #1

- 31

- 0

How do you find the solution tan(x)=sin(2x)?

- #2

cristo

Staff Emeritus

Science Advisor

- 8,107

- 73

Can you express both sides in terms of sin(x) and cos(x)? That might be a good place to start.

- #3

- 31

- 0

No...do i have to do that to find all the solution points?

- #4

- 5,779

- 1,078

You could plot them and look for the intersection points.No...do i have to do that to find all the solution points?

But cristo's suggestion would probably yield more accurate ["closed form"] answers. (Be careful not to inadvertently throw away solutions.)

Last edited:

- #5

danago

Gold Member

- 1,122

- 4

[tex]

\begin{array}{l}

\tan x \equiv \frac{{\sin x}}{{\cos x}} \\

\sin (2x) \equiv 2\sin x\cos x \\

\end{array}

[/tex]

- #6

- 1,728

- 13

square both sides...then make use of (a-b)^2 = (a+b)(a-b)

- #7

- 5,779

- 1,078

um...square both sides...then make use of (a-b)^2 = (a+b)(a-b)

(a-b)^2 = a^2 - 2ab + b^2

a^2 - b^2 = (a+b)(a-b)

- Replies
- 2

- Views
- 9K

- Last Post

- Replies
- 13

- Views
- 971

- Replies
- 2

- Views
- 809

- Replies
- 3

- Views
- 3K

- Replies
- 4

- Views
- 2K

- Last Post

- Replies
- 7

- Views
- 1K

- Last Post

- Replies
- 2

- Views
- 509

- Last Post

- Replies
- 2

- Views
- 5K

- Last Post

- Replies
- 6

- Views
- 6K

- Last Post

- Replies
- 15

- Views
- 2K