Final Cover - For Printing

Therefore, x = 3

log 5 125 = 3

The idea of logarithm is to be explained with examples prepared in braille format.

2. Laws of logarithm

Product rule

The logarithm of a product of positive numbers is equal to the sum of the logarithm

of the factors.

In symbols, log x(AB) = logx A + logx B

Quotient rule

The logarithm of the quotient of two positive numbers is equal to the difference

between logarithm of the numerator and logarithm of the denominator.

In symbols, logx (A/B) = logx A – logx B

Power rule

The logarithm of a number raised to a power is equal to the power times logarithm of

the number.

In symbols, logx (Ap) = p. logx A

Change of base rule

logx A = logy A ×^ logx Y

The above rules may be explained orally with the assistance of text material in Braille.