Question

TI-89 question
I am using my ti-89 to find a trig derivative,
sin^2(x)
it is giving me (pi/90)sin(x)cos(x)

Answer 1

you must be in degrees mode,
the calculator is converting degrees to radians for taking derivative it seems

Answer 2

maybe change it to radian mode and try ?

Answer 3

yes you are correct. I also, had to make sure it was in exact mode.

Answer 4

\(\large (\sin (x~\text{degrees}))' = (\sin (x\times \dfrac{\pi}{180} ~\text{radians}))' = \dfrac{\pi}{180} \cos(x~\text{degrees})\)