12 terms

this is a test where having lots of colors would be useful, because otherwise everything looks confusing.

leg of right triangle is geom mean

btwn piece of hypot next to it and length of full hypot

altitude is geom mean

btwn the 2 pieces of the hypot

trig functions

SOH CAH TOA. that is all.

law of sines

If you know an angle and the measure of opp side:

sinA/a = sinB/b = sinC/c

sinA/a = sinB/b = sinC/c

law of cosines

if you have info about all 3 sides or side angle side:

a^2 = b^2 + c^2 - 2bc(CosA)

a^2 = b^2 + c^2 - 2bc(CosA)

vector

basically, a directed line segment

written like <x,y> (btw this is called component form)

written like <x,y> (btw this is called component form)

magnitude

length of a vector

usually you can use pythagorean theorum to find this.

usually you can use pythagorean theorum to find this.

direction

the angle that the vector makes with a horizontal line. measured clockwise from x axis. usually involves N,S,E,W because Draz likes word problems a lot.

equal vectors

have same magnitude and direction

parallel vectors

have the same or opposite direction

resultant vector

the sum of 2 vectors. you just add them.

direction of resultant vector

tan^-1(x/y)