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math methods help

Show that two vectors, a and b, are parallel if and only if there exists a positive constant λ
such that a = λb. Hint: Vectors are parallel if and only if the angle between them is zero.
Use the dot product.
please help
Original post by tayyy
Show that two vectors, a and b, are parallel if and only if there exists a positive constant λ
such that a = λb. Hint: Vectors are parallel if and only if the angle between them is zero.
Use the dot product.
please help

What do you know about the dot product and angles?
Reply 2
Original post by Smaug123
What do you know about the dot product and angles?

i have beeing making the angle 0 so that it is parallel and subing in values a1, a2, b1, b2
A.B=|A||B|*cos(x)...
Reply 4
Original post by alex2100x
A.B=|A||B|*cos(x)...

yes ive been subbing the values into the equation and then im not really sure where to go from there
Original post by tayyy
yes ive been subbing the values into the equation and then im not really sure where to go from there


Show your working so far...

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