Question

f(x) = tan' x - x is decreasing in
1) (-0, 0) 2) (0, ..) only
3) (-1, 1) only 4) (0, 1)​

Answer 1

Answer:

Given the function,

f(x)=tan

−1

x−x.

Now,

f

′

(x)=

1+x

2

1

−1

or, f

′

(x)=−

1+x

2

x

2

≤0∀x∈R.

This gives the function f(x) is decreasing on R.