Question

TRUE/FALSE

The value 5pi/2 is a solution for the equation...

Answer 1

\[2\sin ^{2}x-\sin x -1 =0\]

Answer 2

@hartnn

Answer 3

did u try plugging in 5pi/2 ?
you can allso solve for sin x if you want...
plug in sin x = y and u get a quadratic in y

Answer 4

Is this right?

\[2\sin ^{2}(90)-\sin(90)-1=0?\] @hartnn

Answer 5

90 ?? 5pi/2 isn't 90 .....

Answer 6

ok, its equivalent to 90, you can use 90 instead

Answer 7

so, whats sin 90 =... ?

Answer 8

sin(90)=1

Answer 9

so, 2 (1) -1 -1
does this = 0 ?

Answer 10

Yes!!

Answer 11

then 5pi/2 is the solution :)

Answer 12

Thanks!!

Answer 13

welcomes !!