- #1

- 107

- 0

3sin(x+10)=4cos(x-10)

I tried changinf everything into tan nothing out. I tried expaning the brackets and collecting like terms, that didnt work out either.

Please help.

- Thread starter brandon26
- Start date

- #1

- 107

- 0

3sin(x+10)=4cos(x-10)

I tried changinf everything into tan nothing out. I tried expaning the brackets and collecting like terms, that didnt work out either.

Please help.

- #2

Astronuc

Staff Emeritus

Science Advisor

- 18,858

- 2,122

cos (a + b) = cos a cos b - sin a sin b

sin (a + b) = sin a cos b + cos a sin b

http://mathworld.wolfram.com/TrigonometricAdditionFormulas.html

- #3

- 107

- 0

Yeh, but I cant simplify anything to solve the problem

- #4

Astronuc

Staff Emeritus

Science Advisor

- 18,858

- 2,122

Then collect terms/coefficients of cos x and sin x.

If one has a form A cos x = B sin x, the tan x = A/B and x = tan

- Replies
- 6

- Views
- 93

- Last Post

- Replies
- 7

- Views
- 3K

- Last Post

- Replies
- 4

- Views
- 1K

- Last Post

- Replies
- 6

- Views
- 2K

- Last Post

- Replies
- 2

- Views
- 6K

- Last Post

- Replies
- 3

- Views
- 1K

- Last Post

- Replies
- 11

- Views
- 754

- Last Post

- Replies
- 3

- Views
- 4K

- Replies
- 4

- Views
- 12K

- Last Post

- Replies
- 4

- Views
- 5K