This problem will review the rules of precedence, i.e. the order in which mathematical operations are performed. You can use parentheses (and also square brackets [ ] and/or curly braces $\lbrace \rbrace$) if you want to change the normal way operations work.

The rules are simple. Exponentiation is always done before multiplication and division, and multiplication and division are always done before addition and subtraction. (Mathematically we say exponentiation takes precedence over multiplication and division, etc.). For example what is 1+2*3?
Note: you must compute this number before entering it into WeBWorK.
1+2*3 =
What is $2\cdot 3^2$?
Note: you must compute this number before entering it into WeBWorK.

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Now sometimes you want to force things to be done in a different way. This is what parentheses are used for. The rule is: whatever is enclosed in parentheses is done before anything else (and things in the inner most parentheses are done first). For example, enter the following expression: $$\frac {1+\log(3)}{2+\sqrt{5}}$$ Hint: this is a good place to use [ ]'s and also to use the "Preview" button.

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Here are some more examples: (1+3)9 =36, (2*3)**2 = 6**2 = 36, 3**(2*2) = 3**4 = 81, (2+3)**2 = 5**2 = 25, 3**(2+2) = 3**4 = 81
(Here we have used ** to denote exponentiation and you can also use this instead of a "caret" if you want). Try entering some of these and use the "Preview" button to see the result. The "correct" result for this answer blank is 36, but by using the "Preview" button, you can enter whatever you want and use WeBWorK as a hand calculator.

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There is one other thing to be careful of. Multiplication and division have the same precedence. For example, what does 2/3*4 mean? (Note that / is the "division symbol", which is sometimes written as a line with two dots. Don't think of / as the horizontal line in a fraction. Ask yourself what 1/2/2 should mean.) Multiplication and divsion are evaluated from left to right, i.e., 2/3*4 means (2/3)*4 or 8/3, IT DOES NOT MEAN 2/12. If you want 2/(3*4) = 2/12, you have to use parentheses.

The same thing happens with addition and subtraction. 1-3+2 = 0 but 1-(3+2) = -4. This is one case where using parentheses even if they are not needed might be a good idea, e.g. write (2/3)*4 even though you could write 2/3*4. This is also a case where previewing your answer can save you a lot a grief since you will be able to see what you entered.
Enter 2/3*4 and use the Preview button to see what you get.