Trig Exam 2 Review

Unless otherwise stated, when the test says "answer needs to be rounded", it means...

"round to the hundredths place"

Period formula for sin and cos

(2pi)/B

(x,y)

(cos t, sin t)

horizontal shift

-C/B

Period formula for finding eq'n from graph

2(x for max - x for min)

The in-out rules for negative

DO NOT swap! They stay the exact same

Example: 3pi/4 ≤ x ≤ 7pi/4

Example: 7pi/4 - 3pi/4 = period

Example: 9|cos(sin^-1 of x/9)|, simplify for x.

Example: 9cosθ (because it said "simplify", not "solve")

Example: pi/2 ≤ x ≤ 13pi/2

Example: H.-shift = pi/2

For Q1 & Q3, ref angle is

inside

For Q2 & Q4, ref angle is

outside

Period formula for tan and cot

pi/B

Theta in radians

s (arc length of theta)/ r (radius)

even f'n is f(-x) = f(x)

sec, cos

odd f'n is f(-x) = -f(x)

sin, tan, cot, csc

inverse function

swapping x and y places in the expression

When calculating arc length or sector area...

the angle must be measured in radians

When working with small angles in circles with large radii...

the arc length can be used to approximate the chord length

Radian measure of a central angle is equal to...

the arc length it cuts off

Rad to deg

x*(180/pi)

Deg to rad

x*(pi/180)

general form for cos/sin curve

y=k+Asin(B(x-h))

A (in this case, amplitude) =

½(Max value - min value)

k

½(max + min)

A (in this case, area sector) =

½r²θ