3.4-3.8 Flashcards
axis’ of sin and cos graphs
x - angle
y - output
regularities of a sin graph
origin (0,0)
max @ 1
amp of 1
midline @ y=0
period 2pi
midline
halfway between max and min
amplitude
distance from midline to max/min
period
length of one complete cycle
frequency
reciprocal of the period
regularities of a cos graph
origin (0,1)
max @ 1
amp of 1
midline @ y=0
period 2pi
sinusoidal function
any function involving the transformations of a sin (or cos)
cos(theta)=
sin(theta + pi/2)
transformations
midline, vertical translation
amplitude, vertical dilation
period, horizontal dilation
vertical dilations: stretches vs. compressions
a>1, stretch
0<a<1 compression
to find b (horizontal dilation)
set given period = 2pi/b
a
vertical dilation (amplitude)
d
vertical translation (midline)
b
horizontal dilation by a factor of 1/b
phase shift of a sinusoidal function
(x+c)
acts opposite how you might think
to find c
see translation from origin, also plug points in to see what works!
b(max+c)=regular x max value
sinusoidal function form
f(theta)=asin(b(theta+c))+d
regular max x values for sin and cos graphs
sin:pi/2
cos:0
d (midline) calculation
max+min/2
a (amplitude) calcuation
max-midline or midine-min
set iterations to
16 (for best accuracy)
sinusoidal regression
enter 16 for iteration, enter data, leave period empty or put given value, calculate
tangent of an angle is also…
the slope of the terminal ray
ratio of the angel’s sine to its cosine values
vertical ray’s slope is…
undefined
horizontal ray’s slope is…
0
positive vs. negative slope quadrants
1: +
between: undefined
2: -
between: 0
3: +
between: undefined
4: -
between: 0
vertical asymptotes of tangents
each half-turn around a circle will create another vertical asymptote
pi/2 and 3pi/2 = regular vertical asymptotes
regular function of a tangent function
f(theta)=atan(b(theta+c))+d
regular values for a tangent
period = pi
no amplitude, no midline
VAs: pi/2+pik
origin @ (0,0)
b for tangents
period=pi/b
c for tangents
phase shift
-c right
+c left
VAs for tangents
pi/2 or 3pi/2 + period*k
coordinates of unit circle
0/2pi - (1,0)
pi/6 - (sqrt(3)/2,1/2)
pi/2 - (sqrt(2)/2, sqrt(2)/2)
pi/3 - (1/2, sqrt(3)/2)
pi/2 - (0,1)
pi - (-1, 0)
3pi/2 - (0, -1)