Notes, solutions of unit 03, General Mathematics 9, for Punjab Curriculum & Textbook Board (PCTB), Lahore. * Express a number in standard form of scientific notation and vice versa.

• Define logarithm of a number $y$ to the base $a$ as the power to which a must be raised to give the number (i.e., $a^x = y \Longleftrightarrow log_ay = x, a > 0, a \neq 1 and y > 0)$.
• Define a common logarithm, characteristic and mantissa of log of a number.
• Use tables to find the log of a number.
• Give concept of antilog and use tables to find the antilog of a number.
• Differentiate between common and natural logarithm.
• Prove the following laws of logarithm
  • $log_a(mn) = log_am + log_an$,
  • $loga (\frac{m}{n} ) = log_am – log_an$,
  • $log_am^n = nlog_am$,
  • $log_am log_mn = log_an$.
• Apply laws of logarithm to convert lengthy processes of multiplication, division and exponentiation into easier processes of addition and subtraction etc.

• Unit 01: Percentage Ratio and Proportion
• Unit 02: Zakat, Ushr and Inheritance
• Unit 03: Business Mathematics
• Unit 04: Financial Mathematics
• Unit 05: Consumer Mathematics
• Unit 06: Exponents and Logarithms
• Unit 07: Arithmatic and Geometric Sequence
• Unit 08: Sets and Functions
• Unit 09: Linear Graphs
• Unit 10: Basic Statistic