How to solve math with Math Notes in Calculator on iPhone

You can solve mathematical expressions, create and use variables, or graph equations, for example, when learning new concepts in class, doing day-to-day budgeting, planning an event, remodeling your home, and more.

You can update values, and choose to show results automatically or as suggestions. You can even use a light background, and a Math Note can include a drawing of the problem.

Here’s how to solve math with Math Notes in Calculator on iPhone.

Note: Math Notes works with common mathematical symbols and the same operations as the scientific calculator, plus select numeric systems for written math and variable names.

Solve expressions

1. Start the Calculator app on your iPhone.
2. Tap the Change Mode button and tap Math Notes.
3. Tap to open a previous Math Note, or tap the New Note button to start a new one.
4. Do any of the following:
   • Type a math expression, then include an equal sign.
   • Tap the Handwriting button, write a math expression horizontally, then include an equal sign.
   • Tap the Handwriting button, write a stack of numbers, then draw a horizontal line below the numbers to add the numbers in the stack. Write a different symbol to the left of each number if you want a different operation.
5. Tap the equal sign to see what Math Notes understood in what you wrote. To correct mistakes, you can fix any of the following:
   • Unrecognized math and unsolvable expressions: Tap any dotted red lines to see details about the error.
   • Ambiguous characters: Tap any dotted blue lines to clarify what you wrote.

In horizontal expressions, Math Notes follows the standard order of operations, so multiplication is completed before addition and subtraction, for example. Put parentheses around expressions you want calculated first. For vertically stacked math, Math Notes evaluates expressions from top to bottom.

Math Notes converts any units and currency in expressions automatically, and you can even mix different systems, like 42 meters + 143 feet. Units and currency available here match those in the Convert mode of the basic or scientific calculator.

Update values

1. Start the Calculator app on your iPhone.
2. Tap the Change Mode button, tap Math Notes, and tap the note you want to update.
3. Do one of the following:
   • Erase the number, then enter a new value.
   • Tap the number, then slide left and right to adjust the value using the scrubber that appears above the number.

Graphs using the values update automatically, and when the value is assigned to a variable, any equations using that variable update their results or graphs automatically, too.

Use variables in expressions and equations

1. Start the Calculator app on your iPhone.
2. Tap the Change Mode button and tap Math Notes.
3. Tap to open a Math Note, or tap the New Note button to start a new one.
4. To declare a variable, type or write a letter or word to use as the variable, followed by an equal sign.
5. Type or write a value or expression after the equal sign to assign a value to the variable.
6. Type or write the variable name in an expression or an equation to use it.

Note: Math Notes reads entries from top left to bottom right, so declare a variable (for example, x = 5) before you use it in an expression (such as x + 10 =). If you write an expression without declaring the variable first, you’ll get an error. Variable names can only contain characters from the Latin alphabet, and you can’t use variables in vertical math.

Use equations with two or three variables to graph in two or three dimensions.

Show results automatically or as suggestions

How your iPhone responds to the math problems you enter in Math Notes is up to you.

1. Start the Calculator app on your iPhone.
2. Tap the Change Mode button and tap Math Notes.
3. Tap to open a previous Math Note, or tap the New Note button to start a new one.
4. Enter text, or tap the Handwriting button and begin writing with your finger.
5. Tap the More button, tap Math Results, and then do one of the following:
   • If you want problems to be solved: Choose Insert Results. Answers appear automatically when you type or write a solvable math problem.
   • If you want suggestions to appear: Choose Suggest Results. When you type or write an equal sign or select a solvable math problem, a Solve button appears that, when tapped, inserts the answer.
   • If you don’t want any math results: Choose Off. Answers don’t appear when you type or write an equal sign after an expression.

Use a light background

By default, Math Notes uses a dark background, though you can switch to a light one.

1. Start the Calculator app on your iPhone.
2. Tap the Change Mode button and tap Math Notes.
3. Tap to open a previous Math Note, or tap the New Note button to start a new one and enter text or write.
4. Tap the More button and tap Use Light Background.

Notes can show lines or grids, too.