Question

The reflex angle x is such that cos x =k, where 0 11 years ago

Answer 1

\[\cos ^{2}x + \sin ^{2}x=1\]
\[\sin ^{2}x= 1 - \cos ^{2}x\]
Therefore, \[sinx = -\sqrt{1-\cos ^{2}x}\]

Answer 2

Why is it negative square root?

Answer 3

+ or - but why arent u finding sinx in terms of k

Answer 4

same thing lol, but why is it - squareroot?

Answer 5

I know it's something because of 0<k<1, but what is that?

Answer 6

a reflex angle is between 180 and 360.

and since cosine is positive ...

the angle is in the 4th quandrant

Answer 7

sin of such an angle will be negative

Answer 8

Thanks.

Answer 9

i see