Answer:
(f + g)(x) = 12x² + 16x + 9 ⇒ 3rd answer
Step-by-step explanation:
* Lets explain how to solve the problem
- We can add and subtract two function by adding and subtracting their
like terms
Ex: If f(x) = 2x + 3 and g(x) = 5 - 7x, then
(f + g)(x) = 2x + 3 + 5 - 7x = 8 - 5x
(f - g)(x) = 2x + 3 - (5 - 7x) = 2x + 3 - 5 + 7x = 9x - 2
* Lets solve the problem
∵ f(x) = 12x² + 7x + 2
∵ g(x) = 9x + 7
- To find (f + g)(x) add their like terms
∴ (f + g)(x) = (12x² + 7x + 2) + (9x + 7)
∵ 7x and 9x are like terms
∵ 2 and 7 are like terms
∴ (f + g)(x) = 12x² + (7x + 9x) + (2 + 7)
∴ (f + g)(x) = 12x² + 16x + 9
* (f + g)(x) = 12x² + 16x + 9