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Why is X to the minus 2nd power equal to 1 over x to the 2nd power?
Wiki User
∙ 14y ago
when a variable is to a negative power, the answer is always the variable with the additive inverse of the power, (ex. -2 changes to 2) and is divided by one.
such as X to the -5 power equals 1 over X to the 5th power. I will use the symbol "^" for power. Let's se a numeric example, with 10 instead of "x". Consider this sequence:
10^3 = 1000
10^2 = 100
10^1 = 10
10^0 = ???
10^(-1) = ???
10^(-2) = ???
How should this sequence be completed? In the left-hand column, the exponent decreases one at a time; in the right-hand column, the number decreases by a factor 10 each time. It seems logical to continue this pattern - so the missing question marks can be replaced by 1, 0.1, and 0.01.
More specifically, several laws for powers continue being valid if these definitions are used (a^0 = 1; a^(-b) = 1/a^b). For example, the addition of exponents: x^a * x^b = x^(a+b) continues being valid, even if a or b, or both, are negative.
It is only defined that way; there is no way to "prove" it. The common definition, however, turns out to be very useful.
Wiki User
∙ 14y ago
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How do you solve x to the 2nd power minus 2x minus 13 equal 0?
Using the quadratic formula, you should get two answers: 1 + sqrt(14) and 1 - sqrt(14).
What is 7 to the 2nd power minus 2 to the 3rd power minus 6?
49 - 8 - 6 = 35
What is 12 minus 4 to the 2nd power?
-4
Which is larger 4.2 or 10 to the second power?
4.2 to the 2nd power is equal to 17.64 while 10 to the 2nd power is equal to 100. The latter is larger.
What is x to the 2nd power minus x minus 56?
x2-x-56 = (x+7)(x-8) when factored
X to the 2nd power minus 4x over x to the second power minus 16 divided by x to the 2nd power plus 2x minus 24 over x to the 2nd power minus 2x minus 24?
Would you mind typing it out for me? I don't quite understand exactly what you are asking. For example, x to the second power minus 4x over x to the second power minus 16 would be... x^2-4x/x^2-16 Do you mind typing it out like that? Because what you wrote makes no sense at all.
What is A to the 2nd power minus 5 times A minus 20?
That depends what the value of A is.
How do you solve x to the 2nd power minus 2x minus 13 equal 0?
Using the quadratic formula, you should get two answers: 1 + sqrt(14) and 1 - sqrt(14).
What is 7 to the 2nd power minus 2 to the 3rd power minus 6?
49 - 8 - 6 = 35
What is 12 minus 4 to the 2nd power?
-4
What is 40t to the 3rd power minus 28t to the 2nd power minus 24t?
That factors to 4t(2t + 1)(5t - 6)
What does 5 to the 2nd power equal?
25
What is 18m to the 2nd power minus 75mn plus 12n to the 2nd power?
That factors to 3(m - 4n)(6m - n)
Which is a factor of x to the 2nd power minus 5x minus 6?
which of the following is a factor of x2 - 5x - 6
Which is larger 4.2 or 10 to the second power?
4.2 to the 2nd power is equal to 17.64 while 10 to the 2nd power is equal to 100. The latter is larger.
What does 2 to the 2nd power equal?
4
What is 35x to the 2nd power minus 44x minus 7?
35x2-44x-7 = (7x+1)(5x-7) when factored
