For the answer to A, add the two functions together. f(x) + g(x) = x^2 -x+3. Substitute 2 in place of x. Your answer is 4-2+3. 2+3=5, your final answer.
For the answer to B, subtract g(x) from f(x). You get x^2-2x-(x+3)=x^2-3x+3. Substitute 3 for x. 3^2-3(3)+3=3.
For the answer to C, multiply the two functions together. (x^2-2x)(x+3)=x^3-2x^2+3x^2-6x=x^3+x^2-6x. Substitute 1 for x. 1^3+1^2-6(1)=2-6=-4
For the answer to D, the answer it undefined because substituting -3 into the denominator (x^2-2x)/(x+3) gives you a value of 0. Division by zero is undefined.
