Question

10sinθ^2+3sinθ-4=0 How many answers would i have? What are the solutions if 0360

Answer 1

solving this gives two solutions and sin has already 2 so 4\[10a^2+3a-4=0\]

Answer 2

Ok so my answers are +1/2 and -4/5

Answer 3

that is my solution when i factor, so what are my solutions to find hte other 2?

Answer 4

\[a=1/2,a=-4/5\]
let \[\sin \theta=a\]

Answer 5

Yes, so that is two. I am confused on how to find the others.

Answer 6

\[\sin \theta=1/2\]
\[\sin \theta =-4/5\]
\[\theta=\sin ^{-1}*(1/2)+360k,k \in \mathbb{Z}\]

Answer 7

and\[\theta=180-\sin ^{-1}(1/2)\]

Answer 8

ah, and then 180- arcsin of -4/5

Answer 9

yes

Answer 10

oh wait, not 180, since it is not positive though

Answer 11

arc sin of 4/5 is 53. So wouldnt you need the solution to be negative?

Answer 12

\[180-\theta+360k\]
k=1

Answer 13

sorry, but i don't understand where the K is coming from

Answer 14

its a general solution if you never did it then you can take it as positive

Answer 15

So would you mind giving me the four solutions? I just want to know how to do this, but i may be understanding what you are saying wrong with the 180-theta+360k

Answer 16

http://www.wolframalpha.com/input/?i=10sin%CE%B8%5E2%2B3sin%CE%B8-4%3D0