8/10/2019 8th Std Formula
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Maths/VIII/Formula All Formulae for Semester Nitesh Matta
Chapter Indices
1.
amx an= am+n
2.
aman= am-n
3.
(a x b)m= amx bm
4.
(am
)n
= amxn
5.
a0= 1
6.
a-m
=
7.
(
)
m=
Arc of Circle
1.
Measure of central angle = measure of opposite
minor arc.
2.
Measure of major arc = 360measure of minor
arc
3.
Measurement of semicircle is 180.
4.
Measure of inscribed angle =
5.
Sum of Opposite angles of cyclic quadrilateral =
180
Compound interest
1.
Simple interest =
Amount = Simple interest + Principle
2.
A = P (1 +
)
n
Compound interest = A
P3.
Compound interest is always greater than
simple interest.
Discount And commission
Discount
1.
Marked price = Printed Price = Listen Price
2.
Discount (Rs) =
x Marked Price
3.
Selling price = Marked PriceDiscount (Rs)
4.
Discount(Rs) = Marked Price
Selling Price (Thisformula has to be used when MP and SP
both
are given)
5.
Discount % =
x 100
Commission
1.
Commission (Rs) =
x SP/CP
2.
Amount received by selling from agent = SP
Commission
3.
Amount paid while buying thing from agent =
CP + Commission
4.
Commission % =
x 100
Volume and Surface Area
Cylinder
1.
V = r2h
2.
Curved Surface area = 2rh
3. Total surface area = 2rr+h
4. Area of base =Area of circle = r2
5.
Circumference of base = 2r
6.
To find the answer in liters, first convert all
dimensions into Cm and solve the problem.
Then divide your final answer by 1000. You will
get your answer now into liters.
Cone
1.
V =
r2h
2.
Curved surface area = rl
3. Total surface area = rr+l
4. L2 = r2+h2
5.
Area of base = r2
6. Area of base =Area of circle = r2
7.
Circumference of base = 2r
Sphere
1.
V =
r3
2.
Total surface area = 4r2
Cost formula
1.
Cost = Rate x Area
Factors of Polynomial
1.
a3+ b3= (a+b) (a2- ab + b2)
2.
a3
- b3
= (a-b) (a2
+ ab + b2
)
