Answers

2015-03-13T14:03:44+08:00

This Is a Certified Answer

×
Certified answers contain reliable, trustworthy information vouched for by a hand-picked team of experts. Brainly has millions of high quality answers, all of them carefully moderated by our most trusted community members, but certified answers are the finest of the finest.
Given f(x) = 2x, g(x) = x + 4, and h(x) = 5 – x3, find (f + g)(2), (h – g)(2), (f × h)(2), and (h / g)(2). To find the answers, I can either work symbolically (like in the previous example) and then evaluate, or I can find the values of the functions at x = 2 and then work from there. It's probably simpler in this case to evaluate first, so: f(2) = 2(2) = 4 g(2) = (2) + 4 = 6 h(2) = 5 – (2)3 = 5 – 8 = –3 Now I can evaluate the listed expressions: (f + g)(2) = f(2) + g(2) = 4 + 6 = 10 (h – g)(2) = h(2) – g(2) = –3 – 6 = –9 (f × h)(2) = f(2) × h(2) = (4)(–3) = –12 (h / g)(2) = h(2) ÷ g(2) = –3 ÷ 6 = –0.5 If you work symbolically first, and plug in the x-value only at the end, you'll still get the same results. Either way will work. Evaluating first is usually easier, but the choice is up to you.
0