Trigonometry Flashcards
1
Q
Arc length formula
A
arc length= radius x angle in radians
2
Q
Area of a sector formula
A
Area= 1/2 x r^2 x angle
3
Q
Small angle approximations for sin
A
sin(x)= x
4
Q
Small angle approximations for cos
A
cos(x)= 1 - x^2/ 2
5
Q
Small angle approximations for tan
A
tan(x) = x
6
Q
1 radian
A
180 degrees / pi
7
Q
Pi radians
A
180 degrees
8
Q
sec(x) formula
A
sec(x)= 1/cos(x)
9
Q
cosec(x) formula
A
cosec(x)= 1/sin(x)
10
Q
cot(x) formula
A
1/tan(x)
11
Q
equation linking sin^2(x) and cos^2(x)
A
sin^2(x) + cos^2(x) = 1
12
Q
equation linking cot^2(x) and cosec^2(x)
A
1+ cot^2(x) = cosec^2(x)
13
Q
Equation linking tan^2(x) and sec^2(x)
A
1 + tan^2(x) = sec^2(x)
14
Q
Equation for tan(x)
A
tan(x) = sin(x) / cos(x)
15
Q
Cosine rule
A
a^2 = b^2 + c^2 - 2bcCosA
