Mangyaring lutasin ang q 70?

Mangyaring lutasin ang q 70?
Anonim

Sagot:

Ang sagot ay #option (2) #

Paliwanag:

Kailangan namin

# (a + b) ^ 3 = a ^ 3 + 3a ^ 2b + 3ab ^ 2 + b ^ 3 = a ^ 3 + b ^ 3 + 3ab (a + b)

Hayaan # a = 8 + x #

at

# b = 8-x #

Kaya, # a ^ (1/3) + b ^ (1/3) = 1 #

Cubing magkabilang panig

# (a ^ (1/3) + b ^ (1/3)) ^ 3 = 1 ^ 3 #

# a + b + 3a ^ (1/3) b ^ (1/3) (a ^ (1/3) + b ^ (1/3)) = 1 #

Samakatuwid, # a + b + 3a ^ (1/3) b ^ (1/3) = 1 #

# 8 + x + 8-x + 3 (8 + x) ^ (1/3) (8-x) ^ (1/3) = 1 #

# 16 + 3 (64-x ^ 2) ^ (1/3) = 1 #

# 3 (64-x ^ 2) ^ (1/3) = - 15 #

# (64-x ^ 2) ^ (1/3) = - 5 #

Cubing magkabilang panig

# 64-x ^ 2 = -125 #

# x ^ 2-189 = 0 #

Ang produkto ng mga ugat ng parisukat na equation na ito ay #=-189#

Ang sagot ay #option (2) #

Sagot:

# -189#.

Paliwanag:

Ang ibinigay na eqn. ay, #root (3) (8 + x) + root (3) (8-x) = 1 ………… (bituin) #.

Cubing, # (root (3) (8 + x) + root (3) (8-x)) ^ 3 = 1 ^ 3 = 1 #.

#:. (root (3) (8 + x)) ^ 3+ (root (3) (8-x)) ^ 3 #

(3) (8 + x)) * (root (3) (8-x)) ((root (3) (8 + x) + root (3) 1 #.

#:. (8 + x) + (8-x) + 3 * root (3) (64-x ^ 2) (1) = 1 ………… dahil, (bituin) #.

#:. 3 * root (3) (64-x ^ 2) (1) = 1-16 = -15 #.

#:. root (3) (64-x ^ 2) = - 5 #.

#:. {root (3) (64-x ^ 2)} ^ 3 = (- 5) ^ 3 #.

#:. 64-x ^ 2 = -125 #.

#:. -x ^ 2 = -189 #.

# o, x ^ 2-189 = 0, o, x ^ 2-0x-189 = 0 #.

#: "The Product of the Roots" = - 189/1 = -189 #.

Kaya, ang tamang pagpipilian ay #(2): -189#.