Trigonometry and Radians Flashcards
1
Q
What is the formula for area of a sector?
A
theta r^2 /2
2
Q
What is the formula for arc length?
A
theta r
3
Q
What is the formula for perimeter of a sector?
A
theta r + 2r
4
Q
How do you change radians into degrees?
A
multiply by 180/pi
5
Q
What is the small angle approximation for Sin(x)
A
sin(x) = x
6
Q
what is the small angle approximation for tan(x)?
A
tan(x) = x
7
Q
what is the small angle approximation for cos(x)?
A
1-(theta^2 /2)
8
Q
What does Sin(2a) equal?
A
2sinAcosA
9
Q
What does Tan(2a) equal?
A
2tanA/1-tan^2A
10
Q
What does cos(2A) equal?
A
Cos^2(A)+Sin^2(A)
1-2sin^2(A)
2Cos^2-1
11
Q
What is the identity for sec^2 ?
A
1+tan^2= sec^2
12
Q
What is the identity for cosec^2 ?
A
1+cot^2=cosec^2
13
Q
What is the formula for cot?
A
cos/sin
14
Q
what is the formula for tan?
A
sin/cos
