About scientific calculator
A scientific calculator handles powers, roots, logarithms and trigonometry, which the basic calculator on your phone cannot.
Key things to remember
- Check whether angles are in degrees or radians before using sin, cos or tan.
- log is base 10 and ln is base e (about 2.718).
- Use brackets to control the order of operations: 2 + 3 × 4 is 14, but (2 + 3) × 4 is 20.
Rounding
Computers store numbers with limited precision, so results such as 0.1 + 0.2 may show tiny errors. Round your final answer sensibly.
A worked example
In degree mode sin(30) is 0.5, while in radian mode it is about −0.988. log(1000) is 3, ln(e) is 1 and 2^10 is 1,024. Putting the angle mode right is the single most common source of wrong answers.
Tips
- Use brackets around negative numbers and fractions.
- Check big results with a rough estimate.
- Clear the calculator before starting a new problem.
