Chapter 4

Question 1

30-60-90 triangle

Answer 1

x, 2x, x√3

Question 2

45-45-90 triangle

Answer 2

x, x, x√2

Question 3

Trigonometric functions (1/2)

Answer 3

SOH-CAH-TOA

Question 4

Trigonometric functions (2/2)

Answer 4

Sin-csc, cos-sec, tan-cot

Question 5

Radian measure formula

Answer 5

Angle = s/r
s = length of the arc
r = radius

Question 6

Relationship between degrees and radians

Answer 6

360°=2π

Question 7

Conversion between degrees and radians

Answer 7

Either π/180 or 180/π

Question 8

Conversion between degrees and radians

Answer 8

Either π/180 or 180/π

Question 9

Common angles

Answer 9

360°=2π
180°=π
90°=π/2
60°=π/3
45°=π/4
30°=π/6

Question 10

Common angles

Answer 10

360°=2π
180°=π
90°=π/2
60°=π/3
45°=π/4
30°=π/6

Question 11

Sector area formula

Answer 11

A = (1/2)(r^^2)(central angle of radian)

Question 12

Angular velocity

Answer 12

w = (number of degrees)/(time)

Question 13

linear velocity

Answer 13

v = s/t

Question 14

Trigonometric functions of angles

Answer 14

! cos = x
sec = 1/x
! sin = y
csc = 1/y
! tan = y/x
cot = x/y

Question 15

Basic trigonometric identities (reciprocal)

Answer 15

sec = 1/cos
csc = 1/sin
cot = 1/tan

sin/cos = tan

Question 16

Pythagorean identities

Answer 16

sin^2 + cos^2 = 1
tan^2 + 1 = sec^2
cot^2 + 1 = csc^2