If f(x)=x+3f(x) = x + 3f(x)=x+3 and g(x)=2x−1g(x) = 2x - 1g(x)=2x−1, find (f+g)(x)(f + g)(x)(f+g)(x).
3x+23x + 23x+2
3x+43x + 43x+4
2x2+5x−32x^2 + 5x - 32x2+5x−3
3x−23x - 23x−2