(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

I'm awful with vectors. I know the dot product rule and the uses to find perpendicular vectors and angles. I know about multiplying vectors (a1b1 + a2b2 + a3b3). I know vector arithmetic.

But i cant do:

r = 8i + 12j + 14k + t(i + j - k)

where t is a parameter

The point A has co-ordinates (4,8,a), where a is a constant. The point B has co-ordinates (b,13,13), where b is a constant. Points A and B lie on the line l1.

a) Find the values a and b

2. Relevant equations

3. The attempt at a solution

Well i presume i need to find the parameter t first... how? I dont have enough information do i?

thanks :)

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# Homework Help: Find perpendicular vectors and angles

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