Right triangle trigonometry

Never use the ___ angle as reference

90 degree

Area of a triangle (new formula)

K=1/2absinC (Units are U²)

SOHCAHTOA

SIN (Opposite/Hypotenuse) COS (Adjacent/Hypotenuse) TAN (Opposite/Adjacent)

cofunctions

Sine(A)=Cosine(B), Sine(B)=Cosine(A) - sinA + cosB = 90

If you don't have a degree(angles) use the....

and Key!!!

Upper case letters represent

angles

reference angle is marked with an

arc

opposite the reference angle is called

opposite

Lower case letters represent

sides

Law of Sines

sinA/a=sinB/b=sinC/c

reference angle

the acute angle formed by the terminal side of an angle in standard position and the x-axis

angle of depression

the angle between the line of sight and the horizontal when an observer looks downward

angle of elevation

the angle formed by a horizontal line and a line of sight to a point above

adjacent side

the side next to the angle of reference

Hypotenuse

the side of a right triangle opposite the right angle

when using Law of sines to find an angle make sure to....

use 2nd sine after you have cross multiplied

Angle Measures using trig

when finding an unknown angle press second and then tan,cos, or sin depending on what sides you have. After that in the parentheses write the sides dividing each other depending on what you used. (this is what it should look like on your paper.... Cosθ=adj/hyp)

theta

θ<---- a variable commonly used in trigonometry to represent an unknown angle