Vector - points in same direction

[marionca57]

I don't know how to make the vector arrow on top of the letter so I just underlined the vectors. Also I don't know how to make the square root symbol so I just type sqrt for it.

Homework Statement

Which points in the same direction as V = (-sqrt2, sqrt3, sqrt5)
a) 1/10 V
b) sqrt10/10 V
c) sqrt10 V
d) sqrt 10 V

Homework Equations

The Attempt at a Solution

I am not sure where to start other than calulating the sqrt of 2,3, and 5. My best guess would be c but I need to know why if that is correct or some help figuring it out.
Please help,
Thanks,
Marion

 

[tiny-tim]

Welcome to PF!

I don't know how to make the vector arrow on top of the letter so I just underlined the vectors. Also I don't know how to make the square root symbol so I just type sqrt for it.

Hi Marion! Welcome to PF!

(have a square-root: √ )

On this forum, type vectors in bold.

Which points in the same direction as V = (-sqrt2, sqrt3, sqrt5)
a) 1/10 V
b) sqrt10/10 V
c) sqrt10 V
d) sqrt 10 V
…
I am not sure where to start other than calulating the sqrt of 2,3, and 5. My best guess would be c but I need to know why if that is correct or some help figuring it out.

(c and d look the same )

As you probably know, on this forum we don't tell you the answer, we just try to nudge you in the right direction.

What tests do you know for two vectors to be pointing in the same direction?

 

[jimvoit]

It is a good idea to make carefull use of parentheses so that there is no
ambiguity as to the meaning of an expression.

Consider that for positive constants k, and vectors v, k v is in the same direction of v.