x 2 x 2 = 1
How many integers of x satisfy the equation above?
Note: 0 0 is undefined.
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There's a simpler approach.
Hint : x 2 x 2 = ( x 2 ) x 2 .
Nice solution sir. But is there any way to prove that these are the only two solutions?
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u can check it out by drawing the graph of y = x 2 x 2 and y = 1 , they both intersect at two integer points 0 and 1
check it out over here
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What about x = − 1
Why doesn't the graph show negative values of x? (Just want to know)
It could be argued that there could be 3 values. -1, 1 and 0.
Here are some sources that suggest that there are some ways that 0^0 = 1
https://www.math.hmc.edu/funfacts/ffiles/10005.3-5.shtml http://mathforum.org/dr.math/faq/faq.0.to.0.power.html http://www.askamathematician.com/2010/12/q-what-does-00-zero-raised-to-the-zeroth-power-equal-why-do-mathematicians-and-high-school-teachers-disagree/
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Officially, 0 0 is undefined.
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You're no fun. Didn't you read any of the links I provided?
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@Norm Nolasco – There is a reason for why the value of 0 0 is undefined.
We know that x 0 = 1 but we also know that is 0 x = 0
From the above points we have two values for 0 0 - 1 and 0. So the value of 0 0 remains undefined.
PS : There might be more ways to prove 0 0 is undefined.But this is the method that i know.
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@Athiyaman Nallathambi – Algebraically, perhaps it should be 1. Using the "official" definition, a x : = e l n x , but ln 0 is undefined.
@Athiyaman Nallathambi – Yes, it "should" be 1, but the official ruling is that it isn't anything at all. In a way it makes little practical difference, anyway.
That's exactly what I thought, but then since it was deemed incorrect, I suggested 2 values, excluding 0^0 .
Why only 1, -1
Note x 2 x 2 = ( x 2 ) x 2 = 1 1 so x 2 = 1 ⇒ x = ± 1 .
Sravanth Chebrolu Proof that the cases are the few ones mentioned in the solution:
Let 0 < a = 1 be another answer (by false assumption).Then we'd have:
a 2 a 2 = 1 → ( 2 a 2 ) l o g a = l o g 1 → ( 2 a 2 ) l o g a = 0
→ 2 a 2 = 0 ∨ l o g a = 0 → a = 0 ∨ a = 1
Which is indeed a contradiction that proves that ∀ a ≥ 0 ↔ a = 0 ∨ a = 1
Also for x < − 1 we'll prove that the equation cannot hold:
x < − 1 → x 2 > 1 → ( x 2 ) x 2 > 1 x 2 = 1 → x 2 x 2 > 1
And hence we're done.
By the way,how are you feeling?Are thing starting to get better?
Well done sir! and yes I'm a lot better now, but it's my father who is still down . . .
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Hope he gets better soon.And please don't call me sir xD, we merely have 2 years in difference!. Call me Arian if you wish.
Well if x 2 x 2 = 1 i f x = 1 , 1 2 = 1 Considering the exponent is two multiplied by a number, and the answer is one, we can assume that the exponent cannot be higher than one. However, we can still test for negative one. x 2 x 2 = 1 , i f x = ( − 1 ) , x 2 x 2 = − 1 2 = 1
0^0 is not undefined. It is 1. The "correct" answer is two, with x being equal to either 0 or 1, but there could also be three solutions, with x being equal to -1.
Similarly we can just simplify it to
x^{2x^{2}} - 1 = 0
And just following through with that and expanding, we have
(x^{x^{2}} + 1) (x^{x^{2}} - 1)
Giving 2 solutions of 1, -1
(xᵡ² + 1)(xᵡ² ̶ 1) = 0 .... maybe that's enough... I hope.
x 2 x 2 = ( x 2 ) x 2 = 1 = 1 1 so x 2 = 1 x = 1 , o r x = − 1 So, they have t w o value
1 and -1 because (-1)^2(-1)^2=1 and also anything power 1 is 1 itself.
Note that if $|x|>1$ , $x^2>1$ and this way, $(x^2)^{x^2}>1$. So, $|x|=1$ because $x$ is a integer number.
Case 1: 1^2*1²=1
Case 2: -1^2*(-1)²=1
0^0 is undefined.
x^(2x^2)=1 or, log(x^(2x^2))=log1 or, (2x^2)logx=0 [as, log1=0] eighther, (2x^2)=0 or, logx=0 or, x=0 or x=1 that means x has two values
There are in fact 2 solutions:
-1,1 are all integers and solve the equation as one can easily verify.
Note: 0 0 is often considered indeterminate.
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Case 1: 2 x 2 = 0
⇒ x = 0 but if x = 0 ⇒ x 2 x 2 = 0 2 ∗ 0 2 = 1
Case 2: x = 1
⇒ x 2 x 2 = 1 2 ∗ 1 2 = 1
Case 3: x = − 1 for even exponent
⇒ x 2 x 2 = ( − 1 ) 2 ∗ ( − 1 ) 2 = 1
So, they have two value.