Question

if sinA=-7/25 where 180 13 years ago

Answer 1

what A did u get ?

Answer 2

-16.26020471

and then i substitute it to tan(A/2) which gave me -1/7
but i doubted my answer because of the 180<A<270, how will i do this? is my answer correct??

Answer 3

-16.2 is in 4th quadrant, not in 3rd

Answer 4

ow.. so there is another value for A? which will be in the 3rd quadrant?

Answer 5

yes.

Answer 6

which i m trying to find

Answer 7

did you got it?? how??

Answer 8

sin(180-(-16.2))=sin(-16.2)=sin(196.2)
so A=196.2

Answer 9

got that^ ?

Answer 10

waa!!.. -7 is the answer??
how did u arrived with the sin(180-(-16.2))?

Answer 11

because sin(180-B)=sin B
so i had sin(-16.2)=-7/25
i wanted to bring the angle in 3rd quadrant, so i used sin(180-B)=sin B

Answer 12

but when 270<A<360, is my answer correct?? -1/7?

Answer 13

yup.
4th quadrant.

Answer 14

owh.. thanks again..! :)) i have more questions.. i'll just post it :))