Find the solution to sqrt(2)sinx+1=0

Question

anonymous · Answer

do u mean $$\sqrt{2} (x) + 1 =0$$

anonymous · Answer

oh, sorrry. it is like that, but with a sin before the x

anonymous · Answer

substract 1 from both sides, divide both sides by root 2. and then sin-1(result)

jim_thompson5910 · Answer

sqrt(2)sinx+1=0


sqrt(2)sinx=-1


sin(x) = -1/(sqrt(2))


sin(x) = -sqrt(2)/2


Then use the unit circle to determine which values of x (or which angles) make this equation true.

anonymous · Answer

so it is 3pi/4?

jim_thompson5910 · Answer

no because sin(3pi/4) = sqrt(2)/2

anonymous · Answer

sorry, didn't see the -

jim_thompson5910 · Answer

no, sin(pi/4) = sqrt(2)/2

jim_thompson5910 · Answer

It turns out that 5pi/4 works though since sin(5pi/4) = -sqrt(2)/2

Remember to look below the x axis on the unit circle (since sine is negative)

anonymous · Answer

would 7pi/4 work as well?

jim_thompson5910 · Answer

yes it would

anonymous · Answer

Thank You!!!

jim_thompson5910 · Answer

Are you solutions restricted to a certain interval?

jim_thompson5910 · Answer

like do you have to keep the solutions within [0,2pi) or something?

anonymous · Answer

I have 7pi/4 as a choice, but i didn't have 5pi/4

jim_thompson5910 · Answer

ah so it's multiple choice, nvm that thought then

anonymous · Answer

Oh ok... thanks for thinking of it anyway though :)

jim_thompson5910 · Answer

you're welcome