cho a⋮b , b⋮c . tim UCLN ( a,b,c ) va BCNN ( a,b,c)

cho a = 45 ; b = 204 ; c = 126

a)tim UCLN (a,b.c)

b)tim BCNN (a,b)

cho a = 45 ; b = 204 ; c = 126

a, tim UCLN_{( a ; b ; c  )}

b, tim BCNN  _{( a ; b )}

cho a/b=15/35,biet UCLN(a,b).BCNN(a,b)=3549

tim (a,b)

1. Tim a,b thuoc so tu nhien 

a. Bcnn(a,b) = 40; ucln =10

b. a - b = 48 , ucln = 12 va 10<a,b<100

c. a x b = 180, ucln = 6

d. ax b = 216, ucln = 6

e. a + b = 128, ucln = 16

2. tim ucln voi n thuoc so tu nhien (ghi cach trinh bay)

14n + 3 va 21n+ 4

Biet rang : BCNN(a,b).UCLN(a,b)

a, BCNN cua hai so la 600, UCLN cua chung nho hon 10 lan BCNN. So thu 1 la 120, tim so thu 2.

b, UCLN cua hai so la 12, BCNN cua chung lon gap 6 lan UCLN . So t 1 la 24, tim so t 2

c, Tong cua hai so bang 60, tong giua UCLN va BCNN cua chung la 84. Tim hai so do.

Tim a,b thuộc N sao . Biết a+b=40 và BCNN(a,b) = 7.UCLN(a,b)

        a,   ab = 360 va BCNN[ a;b] = 60

        b,   UCLN[a:;b] =12 va  BCNN[a;b] = 72

        c,   UCLN[a;b] = 15 va BCNN[a;b]=2100.UCLN[a;b] 

Cau 12 : Cho a=45 ; b=204; c= 126

a) Tim UCLN ( a,b,c) 

b) Tim BCNN ( a,b,c)

         GIUP MINH VOI !