Fien tried to solve the following equation, where x is in degrees to the nearest tenth, in the
interval from -180° to 180°, but she made a mistake.
sin(x) = 0.95
Here is Fien's work.
sin ¹(sin(x))
1.3 + 360n
Using sin(x) = sin(x +360)
x
...358.7, 1.3,361.3...
=
sin ¹(0.95)
1.3
k
Using sin(x)=sin(180-2)
and sin(x) = sin(x+360)
178.7+360n
*...-181.3, 178.7, 538.7...
The solutions to a within the interval from-180° to 180° are 1.3 and 178.7"
What was Fien's mistake?