NTA Abhyas JEE Main2020MathematicsFunctionsPractice
For the function f x = s i n π x × c o s - 1 x , choose the correct option. (where . represents the greatest integer function)
Options
- ADomain of f x ∈ - 1,1
- BRange of f x contains exactly two elements
- Cf x is an identity function
- Df x is a constant function
Correct answer
D. f x is a constant function
Step-by-step solution
For any x ∈ R , we know, sin ⁡ π x = 0 ∴ f x = 0 ,   ∀ x ∈ - 1,2 ∵ - 1 ≤ x ≤ 1   f o r   c o s - 1 x   t o   be   d e f i n ed ∴ Domain x ∈ - 1,2 ⇒ Range = 0 ∴ f x is a constant function