What Is a Scientific Calculator?

A scientific calculator does what a basic calculator does, and adds the functions used in math, science and engineering: trigonometry, logarithms, powers, roots and factorials. It also follows the proper order of operations, so you can type a whole expression at once.

How It Calculates

The calculator works an expression out in this order:

Parentheses and functions such as sin( and √(.
Powers and roots, from right to left, so 2^3² is 512.
Multiplication and division, from left to right. A number next to a bracket or function multiplies, so 2(3+4) is 14.
Addition and subtraction, from left to right.

For example:

2 + 3 \times 4^{2} = 2 + 3 \times 16 = {show('2+3×4²')}

Three rules worth knowing

Negative numbers and powers: −2² is −4, because the power comes first. For the square of −2, use (−2)², which is 4.
Percent: 200 + 10% adds 10% of 200, which gives 220. On its own, or with × and ÷, 10% simply means 0.1, so 200 × 10% is 20.
Precision: answers show up to 12 significant digits. Very large or small answers use EXP form, so 1.5E20 means 1.5 × 10²⁰.

How to Use the Scientific Calculator

"What is the sine of 30 degrees, plus the square root of 16 times 2?" This calculator answers that.

Let's enter it, key by key. Every key can also be used with your keyboard:

Deg: Choose Deg, which measures angles in degrees. Use Rad for radians.
sin: Press sin, 3, 0 and ), which gives the sine of 30 degrees. Brackets left open close by themselves when you press =.
+: Press +, which adds the next part.
√x: Press √x, 1, 6 and ), which gives the square root of 16.
×: Press × and 2, which multiplies the square root by 2 before adding it.

The answer so far appears as you type. Press = to finish, and you get 8.5.

The other keys

sin⁻¹, cos⁻¹, tan⁻¹: find the angle. For example, sin⁻¹(0.5) is 30 degrees, or 0.523598775598 radians.
x^y, x², x³: powers. Press 2, x^y and 10 for 1,024.
^y√x, √x, ³√x: roots. Press 4, ^y√x and 16 for the fourth root of 16, which is 2.
e^x, 10^x, ln, log: ln uses base e and log uses base 10, so log(1000) is 3.
1/x, n!: 4 then 1/x is 0.25, and 5 then n! is 120.
EXP: enters powers of ten. Press 3, EXP and 5 for 3 × 10⁵. Use − after EXP for a small number.
±: changes the sign of the number you just typed.
Rand: enters a random number from 0 to 1.
Ans: uses your last answer. After an answer, pressing an operator such as + carries on from it.
M+, M−, MR: M+ and M− work out the entry and add it to, or take it from, the memory. MR puts the memory into your entry. The × beside the memory clears it.

Calculate and Clear

Press = or Enter to see your answer. If something can't be worked out, such as 1 ÷ 0 or a square root of a negative number, a message explains why in the display, and your entry stays so you can fix it. Back or Backspace removes the last entry. AC or Esc clears everything except the memory and Ans.

Using your keyboard

Click the calculator, then type digits and + - * / ^ ( ) . % !. The functions, such as sin, use the keys on the screen. On a phone, tap Show functions to see them.

For learning and everyday use. For exams or important work, check your results with an approved calculator.