The function f satisfies the functional equation $3f(x)+2f\left(\frac{x+59}{x-1}\right)=10x+30$ for all real x ≠ 1. The value of f(7) is
Answer & explanation
Correct answer: option 2
$3f(x)+2f\left(\frac{x+59}{x-1}\right)=10x+30$
For $x = 7, 3 f(7)+ 2 f(11) = 70 +30 =100$
For $x =11, 3 f(11)+ 2 f(7) =140$
$⇒ f(7) = 4$