Scientific Calculator Guides
The concepts you need to use a calculator accurately, explained with worked examples.
How to Use a Scientific Calculator: Expressions, Ans, Variables and Memory
Learn to enter full expressions, rely on auto-closing brackets, chain results with Ans, store values with STO and M+, and pick NORM, SCI or ENG display, with worked examples.
02Degrees vs Radians vs Gradians: Angle Modes and Common Mistakes
The difference between DEG, RAD and GRAD, conversion formulas, why sin(30) gives −0.988 in the wrong mode, the ° suffix, units of inverse trig results, and when radians are required.
03Logarithms Explained: log, ln, Change of Base and Worked Examples
How to enter log, ln and base-a logs with log(a, x), the change-of-base formula, log rules, and worked pH, decibel, compound interest and half-life examples, plus domain errors.
04Scientific vs Engineering Notation, SI Prefixes and Significant Figures
Scientific notation (a×10ⁿ) versus engineering notation with exponents in multiples of 3, an SI prefix table (k, M, μ, n and more), E-notation input like 6.02E23, and significant-figure rules.
05Order of Operations: −2^2, the 6÷2(1+2) Debate and Calculator Rules
Precedence of brackets, postfix operators, powers, unary minus and multiplication, why -2^2 = -4 but Excel gives 4, right-associative powers, and how SciKey resolves 6÷2(1+2).
06Calculators in Exams: Korean CSAT, Korean Technical Licensing, FE/PE and SAT Rules
Official calculator rules for the Korean CSAT, Korea's national technical qualification exams, NCEES FE/PE and the SAT, with sources, plus practical tips for using a calculator under exam pressure.
07Floating-Point Error on Calculators: Why 0.1+0.2 and sin(π) Look Wrong
Why 0.1+0.2 gives 0.30000000000000004 in IEEE 754 double precision, how a 12-digit display shows 0.3, sin(π) correction, 170! and overflow, the 2⁵³ integer limit, and catastrophic cancellation.