Real math, exactly as you'd write it.

Order of operations

Operators are applied from highest to lowest priority. Operators of equal priority go left to right, except ^, which goes right to left.

Note that −2^2 is −4, as in written maths. Type (−2)^2 to square a negative number. A square root applies to the power that follows it: √2^2 is √(2^2) = 2.

Implicit multiplication

You can leave out × between a number and a constant, a function, a bracket or a root, as you would on paper.

Implicit multiplication has the same priority as ×, so 1÷2π is (1÷2)×π. Write 1÷(2π) if you mean one over two pi.

Percent

On its own or with × and ÷, x% means x ÷ 100. After + or −, it means a percentage of the number before it, like a shop calculator.

Angles & trig

Tap the DEG key (or the chip at the top) to cycle between degrees, radians and gradians. The mode is remembered.

• 2nd turns sin cos tan into sin⁻¹ cos⁻¹ tan⁻¹. It switches off after one key, like a hardware calculator.
• hyp turns them into sinh cosh tanh and stays on until you tap it again. Use both for sinh⁻¹ and friends.
• Inverse functions answer in the current angle mode: sin⁻¹(0.5) is 30 in DEG and 0.523598775598 in RAD.
• Multiples of 30° and 45° are exact: sin(150) is 0.5, cos(90) is 0. try

Powers, roots & logs

Any-base logarithm: use the change-of-base rule, e.g. log base 3 of 81 is log(81)÷log(3) = 4. Odd roots of negative numbers are real: (−8)^(1÷3) = −2. Integer powers stay exact up to 10^9999.

Factorial & combinatorics

x! works for whole numbers up to 3000! and for decimals through the gamma function, so 0.5! = √π ÷ 2. nCr and nPr sit between two numbers.

mod always returns a result with the sign of the divisor: −10mod3 is 2, which is what you want for clock and calendar arithmetic.

Scientific notation

Use 2nd → EXP to type a power of ten: 6.022E23 means 6.022 × 10²³. Press − right after E for a negative exponent, e.g. 1.6E−19.

Results of 10¹⁵ or more, or smaller than 10⁻⁹, are shown in the same E-notation. Settings → Significant digits lets you show 8, 10, 12 or 15 digits. try Nₐ×k

Ans, memory & history

• After =, pressing an operator continues from the answer: × 2 becomes Ans×2. Pressing a digit starts a new calculation.
• Ans always holds the last result. Use it anywhere: √(Ans)+1.
• M+ adds the current result (or the expression's value) to memory, M− subtracts it, MR inserts it and MC clears it. An M chip shows when memory holds a value.
• History keeps 100 calculations. Tap a row to insert its result, or Edit to load the whole expression back.

Editing tricks

• ◀ ▶ move the blinking cursor. New keys go in at the cursor; ⌫ deletes the item before it.
• ⌫ removes a whole function at once, so sin( disappears in one tap.
• Long-press ⌫ to clear everything.
• Missing closing brackets are added for you. They appear faded at the end of the line: (2+3 is evaluated as (2+3).
• Pressing a second operator replaces the first: 5 × + becomes 5+. 5×− is kept, because it means times a negative number.
• Long-press the display to copy the result or paste a number from another app.

Error messages

The error is shown under your expression and nothing is lost. Fix it and press = again.