A community for students.
Here's the question you clicked on:
 0 viewing
anonymous
 4 years ago
solve the following equation for x where
0<or = to x<2pi, sin2x=cosx
anonymous
 4 years ago
solve the following equation for x where 0<or = to x<2pi, sin2x=cosx

This Question is Closed

Mimi_x3
 4 years ago
Best ResponseYou've already chosen the best response.3hint: \(sin2x = 2sinxcosx\)

Mimi_x3
 4 years ago
Best ResponseYou've already chosen the best response.3well where are you stuck or show me what you did

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0the equation is not solved

Mimi_x3
 4 years ago
Best ResponseYou've already chosen the best response.3\[ 2sinxcosx = cosx => 2sinxcosx  cosx = 0 \] why dont you try and solve it

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0take cos(x) you will have \[\Large \cos(x)[2\sin(x)1]=0\] now you have two equations \[\Large \implies \cos(x)=0\] \[\Large \implies 2\sin(x)1=0\] solve these two equations.

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0if i knew how to solve these equations i wouldn;t be asking for help

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0to this stage i know, but how to solve from here?

Mimi_x3
 4 years ago
Best ResponseYou've already chosen the best response.3\[\cos(x) = 0 => cosx = \cos\left(\frac{\pi}{2}\right) => x = \frac{\pi}{2} +n*2\pi , n \epsilon\mathbb{Z} \] \[sinx = \sin\left(\frac{\pi}{6}\right) => x = \left(1\right)^{n}*\frac{\pi}{6} +n*\pi , n \epsilon\mathbb{Z} \]

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0i've been to wolfram alpha to mimi

Mimi_x3
 4 years ago
Best ResponseYou've already chosen the best response.3lol i didnt use wolfram..

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0the answer is correct though but i have to show it using the unit circle, or the graph

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0i think using the sin wave

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0ok let me give you an example then if you have 2cos(x)+1=0 then \[\Large \implies \cos(x)=\frac{1}{2}\] \[\Large x=\cos^{1}(\frac{1}{2})\] there are only two points in 9o.2pi) for which cos(x) is 1/2 they are \[\Large x=\frac{2 \pi}{3}\] \[\Large x=\frac{4 \pi}{3}\] now solve the 2sin(x)1=0 its quite similar to this.

Mimi_x3
 4 years ago
Best ResponseYou've already chosen the best response.3for sinx dw:1345619404355:dw

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0you use wolfram,thats why you are unable to solve these equations by yourself. this wolfram thingy has ruined the students :(. i think at this level students should avoid using that.

Mimi_x3
 4 years ago
Best ResponseYou've already chosen the best response.3yeah i agree. you should only use it to check your answers

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0no i dont use it but i am aware of it

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0mimi you've been great i think i should become a fan
Ask your own question
Sign UpFind more explanations on OpenStudy
Your question is ready. Sign up for free to start getting answers.
spraguer
(Moderator)
5
→ View Detailed Profile
is replying to Can someone tell me what button the professor is hitting...
23
 Teamwork 19 Teammate
 Problem Solving 19 Hero
 Engagement 19 Mad Hatter
 You have blocked this person.
 ✔ You're a fan Checking fan status...
Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.