NTA Abhyas JEE Main2020MathematicsFunctionsPractice
Which of the following is a function whose graph is symmetrical about the origin?
Options
- Af x = 2 x + 2 - x
- Bf x = log x + 1 + x 2 2
- Cf x + y = f x + f y ∀ x , y ∈ R
- DNone of these
Correct answer
C. f x + y = f x + f y ∀ x , y ∈ R
Step-by-step solution
A function whose graph is symmetrical about the origin must be odd. 2 x + 2 - x is an even function. Since, log x + 1 + x 2 is an odd function, ∴ log x + 1 + x 2 2 is an even function. If f x + y = f x + f y ∀ x , y ∈ R , then Put x = y = 0 ⇒ f 0 = 0 Now, put y = - x ⇒ f x + f - x = 0 ∴ f x is an odd function