Paano mo kadalasan ang c² - 12cd - 85d²?

Sagot:

# (c-17d) (c + 5d) #

Paliwanag:

# "gamit ang paraan ng a-c" #

# "ang mga kadahilanan ng - 85 na kabuuan hanggang - 12 ay - 17 at 5" #

# rArrc ^ 2-12cd-85d ^ 2 = (c-17d) (c + 5d) #

Sagot:

# (c + 5d) (c - 17d) #

Paliwanag:

# c ^ 2 - 12 cd - 85 d ^ 2 = (c + ad) (c - bd) #

# => ab = 85, a-b = -12 #

# => a = b - 12 #

# => (b-12) b = 85 #

# => b ^ 2 - 12 b - 85 = 0 #

# "disc =" 12 ^ 2 + 4 * 85 = 484 = 22 ^ 2 #

# => b = (12 pm 22) / 2 = 6 pm 11 = -5 o 17 #

# => (a, b) = (-17, -5) o (5,17) #

# => c ^ 2 - 12 cd - 85 d ^ 2 = (c + 5d) (c - 17d) #