Alicia's Reflection #15

okay so im going to go over some older concepts from the beginning of trigonometry since our midterm is accumulative.

Unit Circle:

90 degs. = (0,1) pi/2

180 degs. = (-1,0) pi2

70 degs. = (0,-1) 3pi/2

360 degs. = (1,0) 2pi


sin=y/r
cos=x/r
tan=y/x
cot=x/y
sec=r/x
csc=r/y

SOHCAHTOA:

S = sin
O = opposite angle
H = hypotenuse
(sin = opposite/hypotenuse)

C = cos
A = adjacent angle
H = hypotenuse
(cos = adjacent/hypotenuse)

T = tan
O = opposite angle
A = adjacent angle
(tan = opposite/adjacent)

*the hypotenuse is opposite the right angle.

*A= 1/2 bh*

*To find the area of a non right triangle use this formula:

*A= 1/2 (leg)(leg)SIN(angle b/w)

*When you have a non right triangle that has pairs, use the law of sines:

Sin A/a = Sin B/b= Sin C/c

*All you are doing is setting up a proportion.

**Remember to solve for an angle, you have to take the inverse.

*To solve a triangle with no angles, use the Law of Cosines:
(opp leg)^2= (adj leg)^2 + (other adj leg)^2 -2(adj leg)(adj leg) Cos(angle b/w)

*use an angle to orient yourself like SOHCAHTOA!!

Hope yall had a good thanksgiving holidays!!