How to Use a Scientific Calculator
Quick Answer: Key Scientific Calculator Functions
| Key | Function | Example |
|---|---|---|
| x² or x^2 | Square a number | 5² = 25 |
| x^y | Raise to any power | 2^10 = 1,024 |
| √x | Square root | √64 = 8 |
| log | Base-10 logarithm | log 1000 = 3 |
| ln | Natural logarithm (base e) | ln(e) = 1 |
| sin, cos, tan | Trigonometric functions | sin(30°) = 0.5 |
| EXP or ×10^x | Scientific notation | 3 EXP 4 = 30,000 |
| n! | Factorial | 5! = 120 |
| ANS | Recalls last answer | Use in next calculation |
For free online versions of every calculation, use the Scientific Calculator and other tools on CalConvs.
Order of Operations: BODMAS / PEMDAS
All scientific calculators follow BODMAS (UK) / PEMDAS (US): Brackets, Orders (exponents), Division, Multiplication, Addition, Subtraction.
- 3 + 4 × 2 = 11 (multiply first: 3 + 8 = 11)
- (3 + 4) × 2 = 14 (brackets first: 7 × 2 = 14)
Always use brackets to force the order you want. They cost nothing and prevent errors.
Powers and Roots
- Square: 5 [x²] = 25
- Cube: 4 [x^y] 3 = 64
- Any power: 2 [x^y] 10 = 1,024
- Square root: [√] 144 = 12
- Cube root: use x^(1/3) on most calculators
- Scientific notation: 3 [EXP] 8 = 3 × 10&sup8; = 300,000,000
Logarithms
- Log base 10: log(1000) = 3 (because 10³ = 1000)
- Natural log: ln(e) = 1
- Log rules: log(A × B) = log A + log B | log(A²) = 2 × log A
- Use LOG for chemistry (pH calculations), acoustics (decibels) and earthquake intensity (Richter scale).
Trigonometric Functions
Always check your calculator is in the right angle mode before using sin, cos and tan.
| Mode | When to Use |
|---|---|
| Degrees (DEG) | Most school-level geometry and everyday angle problems |
| Radians (RAD) | Calculus, physics and university-level mathematics |
- sin(30°) = 0.5 | cos(60°) = 0.5 | tan(45°) = 1.0 (in DEG mode)
- Inverse functions: sin&sup-1;(0.5) = 30°, use SHIFT or 2nd + sin
- Pythagorean theorem: a=3, b=4. c = √(3² + 4²) = √25 = 5
Calculator Use in Exams by Country
- United Kingdom (GCSE and A-Level): Casio fx-83GT CW and fx-85GT CW are the most common permitted calculators. Graphic calculators not allowed in most GCSE exams.
- India (Class 10 and 12): CBSE and most state boards do not permit calculators in board exams. Engineering entrance exams (JEE) are calculator-free.
- Pakistan (Matric and Intermediate): BISE boards generally do not permit calculators in matric exams. Scientific calculators are permitted in higher classes at many institutions.
- United States (SAT and ACT): Calculator permitted on most sections. TI-83, TI-84 and Casio fx-9750 are popular.
- Australia (HSC and VCE): Approved calculators permitted in most exams. CAS calculators allowed in some VCE subjects.
Frequently Asked Questions
How do I calculate e to the power of x on a scientific calculator?
Press [SHIFT] or [2nd] then [ln] to access the e^x function. Enter your x value. For example, e^3 = press [SHIFT][ln] 3 = 20.0855.
Why does my calculator give the wrong answer for sin(90)?
If sin(90) gives a strange answer instead of 1, your calculator is set to Radians mode. Switch to Degrees mode using the MODE or SETUP button. In degrees, sin(90°) = 1. In radians, sin(90) means sin(90 radians) which is approximately 0.894.
How do I enter scientific notation on a calculator?
Use the [EXP] key (sometimes written as [×10^n] or [E]). To enter 4.5 × 10^6: press 4.5 [EXP] 6. Do not type × 10 separately as this gives the wrong result.
Related Tools
- Scientific Calculator: full featured online scientific calculator
- Fraction Calculator: add, subtract, multiply and divide fractions
- Log Calculator: logarithms in any base
- Standard Deviation Calculator: stats calculations for students
- All Math Tools: 46 tools on CalConvs