if -2*-2 is 4 why does -2 squared -4
- (2)^2 = 4 because it's like (-1) x (2)^2
Then why does the Google calculator show this?
http://www.google.com/search?source=ig&hl=en&rlz=1G1GGLQ_ENUS353&q=-2%5E2+%3D+
It is very important to note the difference between
-2^2 and (-2)^2
because of the order of operation, exponents have to be done first, so
-2^2 means -(2x2) = -4
but (-2)^2 = (-2)(-2) = +4
think of algebra,
when you see -2x^2, who is squared ?
Only the x.
in the same way -x^2 really means
-1(x)^2
so -2^2 really means (-1)(2)^2 = -4
Thank you, Reiny. I've been puzzling this problem all evening.
You are so welcome.
The confusion arises because of the negative sign in front of the number. When squaring a negative number, like -2, it's important to understand the order of operations.
To correctly square -2, we follow the order of operations (also known as PEMDAS/BODMAS). According to this rule, the exponentiation (squaring) operation takes precedence over subtraction.
Here's how we get the correct answer:
1. Start by squaring -2: (-2)^2 = (-2) * (-2) = 4.
The result of squaring -2 is 4.
2. Now, let's calculate -2 squared minus 4: -2^2 - 4.
Since squaring (-2) yields 4, the equation becomes:
4 - 4 = 0.
So, -2 squared minus 4 equals 0, not -4. The reason why (-2)^2 and -2^2 give different results is due to the order of operations.