НОК 3 ,6, 9 =18
HOK 10 , 16 ,40 =40
4)26*m*5n=130mn
,5)14a*b*5*c=70abc
6)38*x*2*y*2=152xy
CosABC = (AB*BC)/(|AB|*|BC|)
AB = (3-0, 1-1, 0-(-1)) = (3,0,1)
BC = (1-3, -1-1,2-0) = (-2,-2,2)
|AB| = sqrt(9+0+1) = sqrt(10)
|BC| = sqrt(4+4+4) = sqrt(12)
cosABC = (-6+0+2)/(sqrt10*sqrt12) = -4/(2*sqrt5*sqrt6) = -2/sqrt30
40% это 0,8
100% это х
х=0.8*100/40
х=2
1) 4/57 : 1 2/19 = 4/57 : 21/19 = 4/57 * 19/21 = 4/63
2) 4/63 * 19/64 = 19/1008