Answer:
8.6615988
Step-by-step explanation:
f(x) = 3 sin (x) / ( 1 + cos x)
To find the derivative bottom * d/ dx top - top d/dx bottom all over the bottom squared
d/dx = 3 ( ( 1 + cos x) cos x - sin x( - sin x)) / ( 1 + cos x) ^2
= 3 ( cos x + cos ^2 x + sin ^2 x) / ( 1 + cos x) ^2
= 3 ( 1 + cos x) / ( 1 + cos x) ^2
= 3 / ( 1 + cos x)
Let x = 4
3 / ( 1 + cos 4)
Assuming x is in radians
3/.346356
8.6615988
