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Functional

Every button on the NC Scientific Calculator, explained

Open the Calculator

Trigonometry

sin, cos, tan and their inverses. Every one of these depends on whether the calculator is set to RAD or DEG - try flipping the mode below and watch the answers change.

sinSine▼

The ratio of the side opposite an angle to the hypotenuse, in a right triangle. Type an angle and press compute - the answer changes with the RAD/DEG toggle above.

cosCosine▼

The ratio of the side adjacent to an angle to the hypotenuse, in a right triangle.

tanTangent▼

The ratio of the side opposite an angle to the side adjacent to it. Also equal to sin divided by cos.

sin⁻¹Inverse Sine▼

Also called arcsine. Goes the opposite direction from sin: instead of angle → ratio, it takes a ratio and gives back the angle. Only accepts inputs from -1 to 1.

cos⁻¹Inverse Cosine▼

Also called arccosine. Takes a ratio (-1 to 1) and gives back the angle whose cosine is that ratio.

tan⁻¹Inverse Tangent▼

Also called arctangent. Takes any ratio and gives back the angle whose tangent is that ratio.

Statistics

These three work on a whole list of numbers at once. Type numbers separated by commas.

meanMean (Average)▼

Add up every number in the list, then divide by how many numbers there are.

stdevSample Standard Deviation▼

Measures how spread out a list of numbers is, treating the list as a sample of a bigger population (divides by n−1). Use this one unless a problem specifically says "population."

stdevpPopulation Standard Deviation▼

The same idea as stdev, but for when the list is the entire population, not just a sample of it (divides by n instead of n−1). Gives a slightly smaller number than stdev for the same list.

Counting (Combinatorics)

These answer "how many ways can this happen?" questions.

nPrPermutations▼

The number of ways to arrange r items out of n, where order matters (like 1st, 2nd, 3rd place).

nCrCombinations▼

The number of ways to choose r items out of n, where order doesn't matter (just picking a group). Same numbers as nPr give a smaller answer, since order is no longer counted separately.

!Factorial▼

Multiplies a whole number by every positive whole number below it. Also used inside the nPr and nCr formulas.

Powers & Roots

Exponents and their opposite: roots.

abExponent▼

Raises a number (the base) to a power (the exponent) - multiplies the base by itself that many times.

√Square Root▼

The number that, multiplied by itself, gives you the number under the root.

n√Nth Root▼

A generalized root - set n to 2 for square root, 3 for cube root, and so on.

exNatural Exponential▼

Raises Euler's number, e (see Constants), to a power. Shows up in growth and decay problems.

Other Functions

Rounding, absolute value, and logarithms.

absAbsolute Value▼

Strips the sign off a number, giving its distance from zero. Always comes out positive (or zero).

roundRounding▼

Rounds to the nearest whole number, or - if you give it a second number - to that many decimal places.

lnNatural Log▼

The logarithm base e. Asks "e to what power gives me this number?"

logCommon Log▼

The logarithm base 10 by default. Asks "10 to what power gives me this number?" Set a different base if you need one.

Constants

Two special numbers that show up everywhere in math.

eEuler's Number▼

A special constant, approximately 2.718281828..., that shows up naturally in growth, decay, and compound interest problems. It's the base of the natural log (ln) and the natural exponential (ex).

πPi▼

A special constant, approximately 3.141592653..., equal to the ratio of any circle's circumference to its diameter. Used constantly in circle, angle, and radian problems.

Check Your Understanding

Six questions covering everything above.

Quiz

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