I can't get the correct ans for this question~~

Solve the equation for 0 deg <= theta <= 360 deg.

Printable View

- April 18th 2006, 09:16 AMling_c_0202Solve trig equation
I can't get the correct ans for this question~~

Solve the equation for 0 deg <= theta <= 360 deg.

- April 18th 2006, 10:22 AMThePerfectHackerQuote:

Originally Posted by**ling_c_0202**

But the numerator is expansion of

Thus, you have,

Multiply both sides by a half to get,

But, and (double angles),

Notice the kills the other thus,

Thus,

Thus, all the solutions take the form,

Thus,

You need them to be such as,

For the example the top solution is true only for otherwise it gets too big or too small. Substituting for the top solution we get,

The bottom solution is true only for otherwise it gets too big or too small. Substituting for the bottom solution we get,

Thus,

- April 19th 2006, 09:23 AMling_c_0202
but for the step

it is not given in the question sin 2x <> 0,

how come they could kill each other?

:confused:

is it possible if i 'lost' any solution? - April 19th 2006, 11:41 AMThePerfectHackerQuote:

Originally Posted by**ling_c_0202**

- April 20th 2006, 07:28 AMling_c_0202
:p :D THANK YOU!! :)