y-y1=m(x-x1)
equation of a line with one coordinate and gradient
y=mx+c
equation of a line format
ax+by+c=0
equation if a line where A and B are integers
(x1+x2/2),(y1+y2/2)
Midpoint of a line
√(x1-x2)^2+(y1-y2)^2
length of a line AB
negative reciprocal gradient
perpendicular lines
(x-a)^2 + (y-b)^2 = r^2
equation of a circle with centre (a,b)
(f(x+h)-f(x)/h)
differentiation from first principles
0.5r^2θ
area of a sector
a/sinA = b/sinB = c/sinC
sine rule
a^2 = b^2 + c^2 - 2bccosA
cosine rule for side
cosA= b^2 + c^2 - a^2 /2bc
cosine rule for angles
dy/dx = 0
stationary point
f’’(x) > 0
minimum point
f’’(x) < 0
maximum point