Let f(x)=7x3−2x−12f(x)=7x3-2x-12 and g(x)=−3x3−8x2+10xg(x)=−3x3-8x2+10x . what is the function rule for (f+g)(x)(f+g)(x) ? a: (f+g)(x)=4x6−8x2+8x−12(f+g)(x)=4x6− 8x2+8x−12 b: (f+g)(x)=4x3−8x2+8x−12(f+g)(x)=4x3− 8x2+8x−12 c: (f+g)(x)=4x3−12x2+8x−12(f+g)(x)=4x3 −12x2+8x−12 d: (f+g)(x)=4x6−8x2+12x−12