Question

tìm x

(3x-7)⁵=32

(x-5)⁷=(x-5)⁹(x>hoặc=5)

Answer 1

(3x-7)^5=32

hay (3x-7)^5=2^5

=> 3x-7=2

=>x=3

 

Answer 2

a/ => (3x - 7)⁵ = 2⁵ => 3x - 7 = 2 => 3x = 9 => x = 3

b/ => (x - 5)⁷ - (x - 5)⁹ = 0 

=> (x - 5)⁷ [ 1 - (x - 5)² ] = 0 

=> (x - 5)⁷ (-x² + 10x - 24) = 0

=> (x - 5)⁷ = 0 => x - 5 = 0 => x = 5

hoặc -x² + 10x - 24 = 0 => (6 - x)(x - 4) = 0 

=> x = 6 hoặc x = 4

Vậy x = 4 ; x = 5; x = 6

Answer 3

giai ho minh voi: 2×3^x-5=7^2