SAT 2 Subject test Flashcards
If polynomial P(x) is divided by x-a, what is the remainder?
P(a)
Because P(x)=(x-a)Q(x) + R
at x=a we have P(a)=R
If f(a) = 0 then f(x) has a factor of (x-a)
Polynomial f(x) with a factor of (x-a) can be expressed as
f(x) = (x-a)Q(x)
Therefore, f(a) = 0 means that the remainder is 0
P(x) = anxn + an-1xn-1 + an-2xn-2 + ….+ a1x + a0 = 0
What are the sum and product of the roots?
Polynomial P(x) has one root a+bi, with a and b real numbers, what is the other root?
The conjugate a-bi is also a root of P(x)
What is |a+bi|?
(a2 + b2)1/2
What does the discriminant D tell us for:
- D > 0
- D = 0
- D <0
- Roots are real and unequal
- Roots are real and equal
- Roots are imaginary (no real roots)
For two Linear functions:
y = m1x + b1 and y = m2x + b2
If m1 = m2 and b1 not= b2
The two lines are parallel
For two Linear functions:
y = m1x + b1 and y = m2x + b2
If m1 = m2 and b1 = b2
Then the two lines coincide
For two Linear functions:
y = m1x + b1 and y = m2x + b2
If m1.m2 = -1
Then these two lines are perpendicular
For two Linear functions:
y = m1x + b1 and y = m2x + b2
If m1 not= m2
Then these two lines are intersecting
Distance between point (x1, y1) and a line ax + by + c = 0
D = |ax1 + by1 + c|/(a2 + b2)1/2
Distance between (x1, y1) and (x2, y2)
D = {(x2-x1)2 + (y2-y1)2}1/2
Distance from the origin to a point (a, b, c)
[a2 + b2 +c2]1/2
Standard equation of a circle with center at (h, k) and radius r
(x-h)2 + (y-k)2 = r2
Standard equation of an ellipse with center (h, k) and where a > b
(x - h)2/a2 + (y - k)2/b2 = 1 Major axis is horizontal
(x - h)2/b2 + (y - k)2/a2 = 1 Major axis is vertical
Length of Major and Minor Axes of ellipse?
Major axis = 2a
Minor Axis = 2b
For an ellipse if c is the length from the center to the focus what is its value?
c2 = a2 - b2
Standard form of parabola with vertex at (0, 0)
Vertical axis: x2 = 4py
Horizontal axis: y2 = 4px
Standard form of a hyperbola, center at (0, 0)
Transverse axis horizontal: x2/a2 - y2/b2 = 1
Transverse axis vertical y2/a2 - x2/b2 = 1
Hyperbola Focus for (_+_c, 0)
c2 = a2 + b2
Asymptotes, horizontal and vertical axis for a hyperbola
Horizontal: y = +(b/a)x
Vertical: y = +(a/b)x
What are Domain and Range
Domain is the set of X (input)
Range is the set of Y (output)
What are odd and even functions
Even function: f(x) = f(-x)
Odd function: f(x) = -f(-x)
If p is the period of f(x) then:
f(x + p) = f(x)
If p is the period of f(x) then what is the period of
y = cf(x)
y = f(cx)
Period is p
Period is p/c
If g is the inverse of f, what are the properties?
f(g(x)) = x and
g(f(x)) = x
f-1(x) is the reflection of the graph of f in the line y = x
If point (a, b) lies on the graph of f, then the point (b, a) lies on the graph of f-1
When does an inverse function exist?
When f is increasing on its entire domain
When f is decreasing on its entire domain
Use horizontal line test
If f is continuous on a closed interval [a ,b] and k is any number between f(a) and f(b) then
There is at least one number c in [a ,b] such that f(c) = k
If a polynomial has integer coefficients the possible rational zeros of f are:
(factors or constant term)/(factors of leading coefficient)
For a polynomial with real coefficients and a0 not= 0
- The number of positive zeros of f is either equal to the number of variations in sign of f or less than the number by an even integer
- The number of negative zeros of f is either equal to the number of variations in sign of f or less than the number by an even integer
x → 0 lim (1 + x)1/x
and
x → infinity lim (1 + 1/x)x
e
What is the nth term tn if the first is t1 and the common difference is d
tn = t1 + d(n - 1)
The sum of a finite arithmetic sequence with n terms is
Sn = n(t1 + tn)/2
What is the nth term if the first term is t1 and the ommon ratio is r?
tn = t1rn-1