Ako to urobiť?

Ako to urobiť?
Anonim

odpoveď:

# A = 2 # a # B = 5 #

vysvetlenie:

Tu #A (X-3), ^ 3 + b #

# = A (x ^ 3-3 * x ^ 2 * 3 + 3 * x * 3 ^ 2-3 ^ 3) + b #

# = Ax ^ 3-9ax ^ 2 + 27ax-27a + b #

porovnávanie

# Ax ^ 3-9ax ^ 2 + 27ax-27a + b # a # 2x ^ 3-18x ^ 2 + 54x-49 #,dostaneme

# Rarrax ^ 3 = 2x ^ 3 #

# Rarr = 2 #

a # B-27a = -49 #

# Rarrb-27 * 2 = -49 #

# Rarrb-54 = -49 #

# Rarrb = 5 #

takže, # A = 2 # a # B = 5 #.