Basic Mathematics and Measurements
    1.0 Introduction
    2.0 Trigonometry
    3.0 Basic logarithmic functions
    4.0 Differentiation
    5.0 Integration
    6.0 Graphs
    7.0 Significant Figures
    8.0 Rounding off
    9.0 Errors
    10.0 Combination of errors
    11.0 Length Measuring Instruments
    12.0 Questions

1.1 Mensuration formulae

(A). Circle

Perimeter or circumference $(C)$,

$$C = 2\pi r = \pi D$$

Area $(A)$, $$A = \pi {r^2} = \frac{{\pi {D^2}}}{4}$$


(B). Cylinder

Curved surface area or lateral surface area $(L)$,

$$L = 2r\pi h = \pi Dh$$

Total area of cylinder $(T)$,

Total area $=$ Curved surface area $+$ Cross-sectional area

$$T = 2\pi rh + 2\pi {r^2}$$$$T = 2\pi r\left( {h + r} \right)$$


(C). Sphere

Surface area $(S)$,

$$S = 4\pi {r^2} = \pi {D^2}$$

Volume of sphere $(V)$,

$$V = \frac{4}{3}\pi {r^3} = \frac{1}{6}\pi {D^3}$$


(D). Spherical shell

Surface area $(S)$,

$$S = 4\pi {r^2} = \pi {D^2}$$

Volume of spherical shell $(V)$,

$$V = \frac{4}{3}\pi {r^3} = \frac{1}{6}\pi {D^3}$$

Volume of material used $(V')$,

$$V' = 4\pi {r^2}t$$


(E). Hollow sphere

Volume of hollow sphere $(V)$,

$$V = \frac{4}{3}\pi \left( {R_2^3 - R_1^3} \right)$$


(F). Cone

Curved surface area or lateral surface area $(L)$,

$$L = \pi rl = \pi r\sqrt {{h^2} + {r^2}} $$

where $l = \sqrt {{h^2} + {r^2}} $

Total area of cone $(T)$,

Total area $=$ Curved surface area $+$ Cross-sectional area

$$T = \pi r\sqrt {{h^2} + {r^2}} + \pi {r^2}$$$$T = \pi r\left( {\sqrt {{h^2} + {r^2}} + r} \right)$$

Volume of cone $(V)$,

$$V = \frac{1}{3}\pi {r^2}h$$


(G). Ellipse

Perimeter or circumference of ellipse $(C)$,

$$C = 2\pi \sqrt {\frac{{{a^2} + {b^2}}}{2}} $$

Area of ellipse (A),

$$A = \pi ab$$


(H). Parallelogram

Area of parallelogram $(A)$,

$$A = bh = ab\sin \theta $$

where $h = a\sin \theta $


(I). Triangle

Area of triangle $(A)$,

$$A = \frac{1}{2} \times \left( {{\text{Base}}} \right) \times \left( {{\text{Height}}} \right)$$$$A = \frac{1}{2}ah$$or$$A = \frac{{ab}}{2}\sin \gamma = \frac{{bc}}{2}\sin \alpha = \frac{{ac}}{2}\sin \beta $$


(J). Trapezoid

Area of trapezoid $(A)$,

$$A = \frac{1}{2}\left( {a + b} \right)h$$


(K). Cuboid

Surface area $(A)$,

$$A = 2\left( {lb + bh + hl} \right)$$

Volume of cuboid $(V)$,

$$V = lbh$$

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