Question

find all solutions of the equation sinx+2sin^2 x =0

Answer 1

let
\[sinx=y\]

Answer 2

\[2y ^{2}+y=0\]

Answer 3

\[Y(2y+1)=0\]

Answer 4

\[y=0\]

Answer 5

\[2y+1=0\]

Answer 6

\[y=\frac{ -1 }{ 2}\]

Answer 7

will that be on quad 2?

Answer 8

\[sinx=0 and sinx=\frac{ -1 }{ 2 }\]

Answer 9

then you find your values

Answer 10

how do you find the value of sinx? please help me out.. this will help me for upcoming test

Answer 11

\[\sin ^{-1}(0)=0\]

Answer 12

sinx=-1/2 is pi/6 right ?

Answer 13

@Directrix please can you help him

Answer 14

any help with finding the value of sinx=-1/2

Answer 15

sinx+2sin^2 x =0

2 sin² x + sinx = 0

sinx (2 sinx + 1) = 0

sin x = 0 OR 2 sin x + 1 = 0

sin x = 0 Or 2 sin x = -1

sin x = 0 or sin x = -1/2

Answer 16

What is the solution domain?
Zero to 360 degrees or 0 to 2 pi radians or all Real numbers?

Answer 17

it says all solutions, so im assuming all real numbers

Answer 18

You will need to learn the fundamental trig values.

Answer 19

so it will be -30 right?

Answer 20

sin x = 0

x = ..., -2π, -π, 0, π, 2π,...

Answer 21

or sin x = -1/2
..... -5π/6 ,-π/6, 7π/6, 11π/6, ...

Answer 22

Let's think how to write these in a less messy way:

x = ..., -2π, -π, 0, π, 2π,... Union x = ..... -5π/6 ,-π/6, 7π/6, 11π/6, ...

Answer 23

by messy, you mean writing it in degrees?? ...... sorry for asking to much... im just not good at this chapter and i really need help

Answer 24

See attached file.
Z is the set of integers.
http://www.wolframalpha.com/input/?i=sinx%2B2sin%5E2+x+%3D0

Answer 25

By messy, I mean to write then not individually but in terms of a multiple of an integer. There are are infinitely many solutions.

Answer 26

The first thing that went wrong is that you divided both sides of an equation by a variable and lost half the answers.
See attached file.

Answer 27

The next problem is leaning the values of the trig functions at 0, pi/6, pi/4, pi/3, and pi/2,

Answer 28

i factored it , but is there a better way to do it without losing solutions ?

Answer 29

so what other options do i have besides factoring ?

Answer 30

If the expression will factor, do that.

You can take y² = y and divide both sides by y to get y = 1 IF you also remember that y could be equal to zero.

I always factor.

If such an equation is quadratic in degree and will not factor, you can always use the Quadratic Formula.

Answer 31

so what is the proper way to solve this equation? im confused now.. is telijahmed's work wrong? if so, how do you solve it ?

Answer 32

This is correct work.

Answer 33

Solutions

Answer 34

ok, and from that how do you find all the value of sinx=-1/2

Answer 35

please help.....