Trig, logs, powers and roots. Type with your keyboard or tap the keys.
Expressions follow the standard order of operations: parentheses first, then factorials and percents, then powers (evaluated right to left, so 2^3^2 = 2^9 = 512), then multiplication and division, then addition and subtraction. A minus sign in front of a power applies after the power, so −2² = −4.
Type numbers in scientific notation with an e: 3e8 means 3 × 10⁸ and 6.6e-34 means 6.6 × 10⁻³⁴. An e that isn't followed by a power is Euler's number, so 2e means 2 × 2.718…
Computers store decimals in binary, which leaves tiny rounding errors. To hide them, results are rounded to 12 significant digits, a sum or difference more than a trillion times smaller than the numbers involved is shown as 0 (so 0.1 + 0.2 − 0.3 = 0), and trig results within 10⁻¹⁵ of zero are shown as 0 (so sin 180° = 0).
Why does sin(90) give 0.89 instead of 1?
The calculator is in radian mode. Tap the DEG/RAD key so it shows DEG, and sin(90) will return 1.
Can I skip the multiplication sign?
Yes. Implied multiplication works, so 2π, 3(4+5) and 2sqrt(9) are all understood.
What does the % key do?
It divides the number in front of it by 100, so 50% becomes 0.5 and 200 × 15% equals 30.