Unit Circle
If a point (x,y) lies on the unit circle, what equation must it satisfy?
x2 + y2 = 1
How do you find an x-intercept of a function?
Set y=0 and solve for x.
Standard form of a parabola opening up or down?
(x−h)2=4p(y−k)
Product Rule of Logs?
log(ab) = loga + logb
Factor Theorem?
If (x−c) is a factor, then f(c)=0.
How do you find a missing coordinate on the unit circle?
Use x2 + y2 = 1 and solve for the missing value.
How do you find the y-intercept of a function?
Evaluate f(0).
How is the focus related to the vertex in a parabola?
Focus is p units from the vertex along the axis of symmetry.
Quotient Rule of Logs?
log(a/b) = loga - logb
If (x+4) is a factor, what must be true?
f(−4)=0.
What are the coordinates of the unit circle at 225 degrees or (5π/4)?
(−sqrt(2)/2,−sqrt(2)/2)
What transformation does f(x+4) represent?
Shift left 4 units
How is the directrix related to the vertex?
It is ppp units from the vertex opposite the focus.
Power Rule of Logs?
log(an) = nloga
Remainder Theorem?
The remainder when dividing by (x−c) equals f(c).
What is cos(5π/4)?
−sqrt(2)/2
What transformation does f(x)+4 represent?
Shift up 4 units
Standard form of an ellipse?
(x−h)2/a2 + (y−k)2/b2 = 1
Compound interest formula (annual compounding)?
A=P(1+r)t
What determines polynomial end behavior?
Degree and leading coefficient.
What is sin(5π/4)?
-sqrt(2)/2
What does (h,k) represent in y=a∣x−h∣+k?
The vertex
How do you identify the center of an ellipse?
From (h,k).
How do you solve exponential equations with the variable in the exponent?
Use logarithms.
What is k(0) for a polynomial?
The constant term