Graphs + Coordinates Flashcards
1
Q
Midpoint
A
(x1+x2 / 2, y1+y2 / 2)
2
Q
Gradient
A
m = dy/dx
3
Q
Perpendicular gradients: If m1 and m2 are perp
A
m1 = -1/m2
4
Q
Equation of a line
A
y-y1 = m(x-x1)
5
Q
Discriminant rules
A
Discriminant = b^2 - 4ac
Greater than 0, 2 roots
Equal to 0, repeated roots
Less than 0, no real roots
6
Q
y = k/x
A
Right hourglass graph
7
Q
y = -k/x
A
Left hourglass graph
8
Q
y = k/x^2
A
Upwards point graph
9
Q
y = -k/x^2
A
Downwards point graph
10
Q
sin graph
A
Period of 360, wave is 0 at 0
11
Q
cos graph
A
Period of 360, wave is 1 at 0
12
Q
Tan graph
A
Period of 180, asymptotes at -90 +- 180n
13
Q
f(x) + a
A
Vector (0 a)
14
Q
f(x+a)
A
Vector (-a 0)
15
Q
af(x)
A
Vertical stretch by sf a
16
Q
f(ax)
A
Horizontal stretch by sf 1/a
17
Q
-f(x)
A
Reflection in x axis
18
Q
f(-x)
A
Reflection in y axis
19
Q
mod(f(x))
A
Below x axis reflects up
20
Q
f(mod(x))
A
Right of y axis reflects left
