Page 3 - ACE YR IGCSE A TOP APPR' TO MATHS

List of Important Formulae

Number

Simple interest
PRT
l =
100
Penerbitan Pelangi Sdn Bhd. All Rights Reserved.
P = Principal
R = Rate of interest
T = Period of time
Compound interest
( R ) n
A = P 1 + 100
P = Principal
R = Rate of interest
n = Period of time
Speed, distance and time
Distance
Speed =
Time
Total distance
Average speed =
Total time

Proportion
Directly proportional
y = kx
Indirectly proportional
k
y =
x
Algebra

The law of indices
x × x = x a + b
a
b
x ÷ x = x a – b
a
b
(x ) = x
ab
a b
x = 1
–a
x a
a
b
x = √x
a
b
x = 1
0
Quadratic formula
–b + √b – 4ac
2
x =
2a
Regular polygons
Interior angles Exterior angles
Total angle (n – 2) × 180° 360°
Each angle (n – 2) × 180° 360°
n n
List of Important Formulae v

List Of Important Formulae.indd 5 15/03/2022 10:33 AM