We don't plug in our answers so I don't know how to that in trigonometry. It does state what x equals i just left that part out becaus I am more interested in why we got different answers.Did you plug in your answers and verify that they don't work??
Did you notice that the real result does not state what x equals!!! So how could it possible be correct????
What was the question?How could this possibly be incorrect? Please enlighten me. The real result is: 2sin(3x/2)*2cosx*cos(x/2)
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Double-check your solution for the roots of [imath]\cos x = -\frac{1}{2}[/imath].they seem
Find x of courseWhat was the question?
You did NOT tell us.
What were you asked to FIND (to do) ?
I did. It seems correct to me. Is it not?Double-check your solution for the roots of [imath]\cos x = -\frac{1}{2}[/imath].
When you said "The real result is: 2sin(3x/2)*2cosx*cos(x/2)", it was NOT clear what the actual question was. You "of course" is rather rude!Find x of course
Oh, sorry, I didn't not intend to be rude. English is not my first language, we use to meaning of 'of course' not to be mean but just to clarify something.When you said "The real result is: 2sin(3x/2)*2cosx*cos(x/2)", it was NOT clear what the actual question was. You "of course" is rather rude!
No, it is not: [imath]\cos \frac{3\pi}{4} \neq \frac{1}{2}[/imath]I did. It seems correct to me. Is it not?
Can you post the exact question please? Does it say "Solve the equation"?
What we need to figure out is, if the exercise said to solve the equation for x, what in the world could they mean by saying that the "result" (solution?) is an expression in x. This is why it makes no sense for you to say,How could this possibly be incorrect? Please enlighten me. The real result is: 2sin(3x/2)*2cosx*cos(x/2)
Others are working on helping you correct your solution; but can you please tell us how you came to the conclusion that 2sin(3x/2)*2cosx*cos(x/2) is "the real result"?Find x of course
oh okay,What we need to figure out is, if the exercise said to solve the equation for x, what in the world could they mean by saying that the "result" (solution?) is an expression in x. This is why it makes no sense for you to say,
Others are working on helping you correct your solution; but can you please tell us how you came to the conclusion that 2sin(3x/2)*2cosx*cos(x/2) is "the real result"?
Also, you should know that there are other questions to ask about an equation besides to find x! Just stating the equation does not imply the question. We've had other cases just recently where the question was not what was assumed.
Who says you are supposed to get that? (And that is not what you get in the end; in the end you get the solutions!) So someone showed you work that led to different solutions by way of this expression? Then they are wrong! And I have no idea how they got that, but there are typically different ways to get the same solution, so their expression being different from yours does not in itself mean your work is wrong.oh okay,
so the question was to determine x. As you can see in the end I got sinxcosx*(4cosx+2), which resulted in certain x values (one of which is incorrect, sorry about that), the result i am supposed to get is 2sin(3x/2)*2cosx*cos(x/2) which results in different x values. I thought it would result in same x values. So I am not particularly sure where I went wrong.
You haven't corrected your solution, but presumably you have realized that rather than [imath]x=\pm\frac{3\pi}{4}+2k\pi[/imath], you should have had [imath]x=\pm\frac{2\pi}{3}+2k\pi[/imath], right?(one of which is incorrect, sorry about that)