1. which expression is equal to (f+g) (×) f (x)=x^2+3; g (x)=x-1a. x^3-3b. x^2-2x+4c. x^2+x+2d. x^3-x^2+3x-32. which expression is equal to (fog)(x) f (x)=3x; g (x)=4x^2+1a. 12x^3+3xb. 4x^2+3x+1c.12x^2+3d. 36x^2+13. f (x)= 2x-8; g (x) = x-5what is the value of (gof)(6)a. -6b. -1c. 1d. 64. f(x) =5x-10 what is the value of f^-1 (-3)a. -5b. 1.4c. 9.4d. -25