3-8 Squares And Square Roots

3-8 Squares and Square Roots

Things to know Taking the square root of a number is the inverse (opposite) of squaring the number Every positive # has two 6² = 36 √36 = 6 square roots, one + and one -. One square root of 16 is 4, since 4 x 4 = 16. The other square root of 16 is -4 since (You can the square root of 4)(-4) is write also 16. 16 as ± 4, meaning positive or negative 4.

Things to know When you press the √ on the calculator it only gives you the nonnegative square root. This is called the Principal square root. √-49 and -√49 are not the same. A negative number has no real square root. A perfect square is a number that has integers as its square roots. They are…. 1 3 9 1625 36 49 64 81 , , , , , , , , …

Things to know In the order of operations, a square root symbol is like an exponent. PEMDAS Everything underneath the square root symbol is treated as if it were in parentheses 2

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Try these Find the two square roots of each number 64 ±8 1 ±1 121 ±11

Evaluate expressions containing square roots 2 2(4) + 5 8+5 13 +7 +7 5+7 12

evaluate the square root first

Practice

Practice