[tex]\bf \begin{cases} f(x)=x^2+1\\ \cline{1-1} g(x)+x=3\\ g(x) = 3-x \end{cases} \\\\[-0.35em] ~\dotfill\\\\ \begin{array}{llll} \boxed{a}\\\\ (f+g)(x)\implies f(x)+g(x)\\\\ (x^2+1)+(3-x)\\\\ x^2-x+4\\ \cfrac{}{} \end{array}~\hfill \begin{array}{llll} \boxed{b}\\\\ (f+g)(-2)\\\\ (-2)^2-(-2)+4\\\\ 4+2+4\\\\ 10 \end{array}~\hfill \begin{array}{llll} \boxed{c}\\\\ (f-g)(x)\\\\ (x^2+1)-(3-x)\\\\ x^2+x-2\\ \cfrac{}{} \end{array}[/tex]
