Can anybody help me with this equation? I am staring to think there is a mistake there....

I tried to factor it, but it does not seem right...

2sin^2(x) - 6sin(x)- 3=0

Printable View

- July 17th 2010, 03:04 PMAngie80Trigonometric equation
Can anybody help me with this equation? I am staring to think there is a mistake there....

I tried to factor it, but it does not seem right...

2sin^2(x) - 6sin(x)- 3=0 - July 17th 2010, 03:11 PMAlso sprach Zarathustra
Hint:

Quadratic equation. - July 17th 2010, 03:23 PMe^(i*pi)
Hint 2:

- July 17th 2010, 03:36 PMAngie80
This is what I tried:

sinx=t

2t^2-6t-3=o

I used quadratic formula, and got:

t= ( 3- √15) /2 = -0.43

What now? I could substitute t for sinx now, but it does not help... - July 17th 2010, 04:18 PMmr fantastic
- July 17th 2010, 04:50 PMAngie80
So, I calculated it and got appx: -26

I must be missing something, because I really do not know how to proceed from here... :(

I know how to use unit circle, but what is value of x, when sinx=-26??

I am veeery confused now.... - July 17th 2010, 06:49 PMmr fantastic
- July 17th 2010, 06:52 PMAngie80
Thanks soooo much!