mmmmaaaaarrrrrrryyyyyyyy

This week we learned about chapter 12 and did a billion aleks.

Here are some random notes that i remember because i'm pretty sure i aced that test.

the symbols for absolute value mean the magnitude, which is where you square each term, then take the square root of that number.
l<5,4>l
5^2+4^2=25+16=41
square root of 41 is the magnitude of your vector.

then there's dot product, which they indicate by putting a dot inbetween two vectors. this gives you a number, NOT A VECTOR. hahaha.

<8,0> . <1,2>
then you just multiply across and you may be tempted to believe the numbers multiply across and then stay as a vector, but no, you have to add them.
if the dot product of two vectors equals zero, then they are perpendicular. just thought you'd like to know.
answer 8

they could also ask you to find the cos of the angle between two vectors, but don't fret, its easy if you recognize the examples above.
its the dot product of the vectors over the magnitude of each vector multiplied. you can figure it out by yourselfffffffffff.