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