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Why does -2^2= -4 but (-2)^2= 4?

User Ldot
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2 Answers

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Explanation:

The minus in (-2)^2 is enclosed in parentheses, so it is also squared:

minus × minus = plus

And talking about this one: -2^2, the minus is not included in the parentheses, that's why we only square the number (2 in this case) and keep the minus in front of it

I hope this will help...

User Sambold
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Answer:

The reason why -2^2=-4 and (-2)^2=4 is due to the rules of mathematical operations and the order of operations, also known as PEMDAS (Parentheses, Exponents, Multiplication and Division, Addition and Subtraction).

According to the order of operations, when you have an expression with multiple operations, you must perform the operations in a specific order. Exponents come before multiplication and division, and before addition and subtraction.

So, when evaluating -2^2, you first evaluate the exponent, which is 2. However, the negative sign in front of the 2 is not part of the exponent, but rather an arithmetic operation. Therefore, the expression is equivalent to -(2^2), which is equal to -4.

On the other hand, when evaluating (-2)^2, the parentheses indicate that the negative sign is part of the base, so you must first evaluate the base, which is -2, and then apply the exponent of 2. This gives you (-2)^2 = 4.

User Totalitarian
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