Trig
sin(30º)
0.5
(n+1)(n)/2
x > 0
∏
Pi = 3.14159...
Sum of angles
180º
cos(a) = ?
a/h
Pythagorean theorem
a2+b2=c2
x2+3x+2 ≥ 0
x ≤ -2, x ≥ -1
e
e = 2.7186...
Triangle inequality 1
a ≥ b+c
tan(a) = ?
(using trig functions)
sin/cos
Euler's theorem
ei∏ + 1 = 0
(3x+1)/(2x-1) > 0
x < -1/3, x > 1/2
θ
θ = An angle
Triangle inequality 2
The biggest angle is across from the longest side
Area of a Triangle using sines and cosines
a*b*sin(c)/2
Solve: Ax2+Bx+C=0
x = (-B±√B̅2-̅4̅A̅C̅)/2A
2x2+1 > 0
x∈ℝ
∑
Summation
30 60 90 triangle sides ratio
a:b:c
√3:1:2
CALCULATORS ALLOWED:
Given △ABC, AC = 12, AB = CB = 10.
Find ∠A, ∠B, ∠C (Approx.)
A: 53.13º, B: 73.74º, C: 53.13º.
Law of cosines
c2=a2+b2-2ab*cos(C)
(3+x)2(x-2)3(5-x)4
---------------------- ≥ 0
(32+x)3(30+x)2(x2+1)
x ≥ 2, x < -32, x = -3
ℵ0
Aleph-null, countable infinity
Prove Triangles 100.
If you make parallel lines, one on the point of the triangle and one on the segment below, you can use theorems to prove.