Question

Tìm bộ chung ( BC ) : 

a. BC ( 84, 108 )

b. BC ( 98, 72, 42 )

c. BC ( 68, 208, 100 )

Answer 1

a: \(84=2^2\cdot3\cdot7;108=3^3\cdot2^2\)

=>\(BCNN\left(84;108\right)=2^2\cdot3^3\cdot7=756\)

=>\(BC\left(84;108\right)=\left\{756;1512;2268;...\right\}\)

b: \(98=2\cdot7^2;72=2^3\cdot3^2;42=2\cdot3\cdot7\)

=>\(BCNN\left(98;72;42\right)=2^3\cdot7^2\cdot3^2=3528\)

=>\(BC\left(98;72;42\right)=\left\{3528;7056;...\right\}\)

c: \(68=2^2\cdot17;208=2^4\cdot13;100=2^2\cdot5^2\)

=>\(BCNN\left(68;208;100\right)=2^4\cdot13\cdot5^2\cdot17=88400\)

=>\(BC\left(68;208;100\right)=\left\{88400;176800;...\right\}\)