NDA2017MathematicsFunctionsActual
Let f( a )= a -1 a +1 . Consider the following : 1) (f(2 a)=f(a)+1 ) 2) (f ( 1 a )=-f(a) ) Which of the above is/are correct?
Options
- A1 only
- B2 only
- CBoth 1 and 2
- DNeither 1 nor 2
Correct answer
B. 2 only
Step-by-step solution
aligned & f ( a )= a -1 a +1 & f (2 a )= 2 a -1 2 a +1 aligned f ( a )+1= a -1 a +1 +1= 2 a a +1 So, f (2 a ) f ( a )+1 Now, f ( 1 a )= 1 a -1 1 a +1 = 1- a 1+ a =- ( a -1 a +1 )=- f ( a )