Question

O ponto P= (1,2,3) pertence a reta: A) X= (1,2,3) + m. (2,0,3) B) X = (3,-2,5) + n.(1,4,2) C) x = (5,3,1)+ m. (1,2,3) D) x = ( -2,4,0) + n.( 3,1,2)

Answer 1

 P= (1,2,3)

 

 A) X= (1,2,3) + m. (2,0,3)

 

1+ 2.m=1  => 2m =0  => m=0

2+m.0=2=>m=0

3+3.m=3=> 3m=0  => m=0

 

B) X = (3,-2,5) + n.(1,4,2)

 3+n.1=1=>n=2

-2+4n=2=>n=1

 5+2n=3=>n=1/2

 

C) x = (5,3,1)+ m. (1,2,3)

 

5+m.1=1=>m=-1/5

3+2m=2=> m=-1/2

1+3m=3=>m=3/2

 

D) x = ( -2,4,0) + n.( 3,1,2)

 

-2+3n=1=>n=1

 4+1.n=2=>n=-2

 0+2.n=3=>n=3/2

 

 

Só a primeira pertence a reta as restantes não existe.