Question

3 f(x) + 2 f(-x) = 2x + 4
f(x)=?
f:R->R

Answer 1

Consideram f(x) = ax+b. trebuie sa aflam a si b
3(ax+b) + 2(-ax+b) = 2x+4

3ax + 3b - 2ax + 2b = 2x + 4
ax + 5b = 2x + 4 => a = 2
                               5b = 4 => b = 4/5

Deci f(x) = 2x + $\frac{4}{5}$