Question

find (f•g) (k) equations in red letters

Answer 1

The answer is (f . g)(x) = - (34k + 17k⁷ + 17k⁵ + 40k³ + 20k² + 60).

Remember that :

(f . g)(x) = f(x) × g(x)

Hence :

• (f . g)(x) = (2k³ + k² + 3)(-17k⁵ - 20)
• (f . g)(x) = -34k⁸ - 17k⁷ - 17k⁵ - 40k³ - 20k² - 60
• (f . g)(x) = - (34k + 17k⁷ + 17k⁵ + 40k³ + 20k² + 60)