i need help with questions 12 and 13 please i dont understand this at all
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Answer:
3rd and 4th options
Step-by-step explanation:
(12)
(f + g)(x)
= f(x) + g(x)
= x - 2 + 5x - 1 ← collect like terms
= 6x - 3
(13)
(g • f)(x)
= g(x) × f(x)
= - 3x(6x² - 3x) ← multiply each term in the parenthesis by - 3x
= - 18x³ + 9x²