Question

gia tri nguyen cua x thoa man (3x-4)^5=(3x-4)^7

Answer 1

=>(3x-4)^5-(3x-4)^7=0

=>(3x-4)^5-(3x-4)^5.(3x-4)^2=0

=>(3x-4)^5.[1-(3x-4)^2]=0

=>(3x-4)^5=0=>3x-4=0=>3x=4=>x=4/3

hoặc 1-(3x-4)^2=0=>(3x-4)^2=1=>3x-4=1 hoặc 3x-4=-1

=>x=5/3 hoặc x=1

mà x nguyên nên x=1