Exponent Definition and 212 Threads

  1. P

    Comparing Exponentiation: 20^100 vs. 400^40?

    Homework Statement Without using a calculator and without evaluating expressions, determine which is greater. 20^100 or 400^40 Homework Equations None, however some exponent laws and possibly mental math are applicable. The Attempt at a Solution I don't know how to reach an answer without...
  2. P

    Exponent Laws Related Homework Question

    Homework Statement For which non-zero value of x is the equation -x^ -4 = (-x)^ -4 true? Explain. Homework Equations None. Other than applicable exponent laws. The Attempt at a Solution I know how to use the guess and check method. But I was wondering how to reach the answer faster and how...
  3. S

    MHB How this exponent expression is reduced

    Initially the expression A has 8 terms. So how is it reduced in the second line to 5 terms? Could you show me, please? Thank you. \begin{align*} A&=10^{28} -10^{22} +61\times10^{14}+12\times10^{21}-12\times10^{15}+3\times10^{9}-36\times10^{8}+9\times10^{2}\\ &=10^{28}...
  4. H

    MHB What algebra rule is used here to give the exponent 2 in step 2?

    First it starts as r= p* (50K^-.5 100^.5) then K=[(50p100^.5/r]^2 So how does the power of 2 get there in the second part when moving K to the other side?
  5. L

    Lyapunov exponent -- Numerical calculations

    In computational physics is very often to calculate largest Lyapunov exponent. If largest Lyapunov exponent ##LE## is positive there is chaos in the system, if it is negative or zero there is no chaos in the system. But what can we say about some certain value of ##LE##. For example...
  6. M

    How Do You Calculate Matrix Powers and Roots?

    Homework Statement I. 3*3 matrix A (8 2 -2, 2 5 4, -2 4 5) II. 3*3 matrix (1 2 0, -1 -2 0, 3 5 1) Homework Equations I. Solve Aexp 100 of 3*3 II. Find the 5th rooth of B matrix The Attempt at a Solution I. I got stuck at diagonalising the matrix. Is this OK 1st step ? If yes...
  7. mhsd91

    The Matrix Exponent of the Identity Matrix, I

    So, essentially, all I wonder is: What is the The Matrix Exponent of the Identity Matrix, I? Silly question perhaps, but here follows my problem. Per definition, the Matrix Exponent of the matrix A is, e^{A} = I + A + \frac{A^2}{2} + \ldots = I + \sum_{k=1}^{\infty} \frac{A^k}{k!} =...
  8. Prof. 27

    Logarithm Issue. Unable to find answer sheet answer

    Homework Statement log39x4 - log3(3x)2 The answer sheet says that the answer is 0, but when I work the problem both ways I get: 2log3x Any ideas? Homework Equations logxy/z = logxy - logxz The Attempt at a Solution Formula Sheet 20-30 Minutes of Messing around with the problem
  9. B

    How TI-89 Calculator Rearranged Exponent Confusion - Ben

    My TI-89 calculator rearranged $$ 2^{2m+1}-1$$ to $$ 2\times 4^m - 1 $$ I can't for life of me work out how it did it. Is anybody able to put me out of my misery? Thank you in advance! Ben
  10. T

    MHB How to calculate binomial (n choose k) coefficients when exponent is negative?

    I'm using Pascal's (n choose k) method for calculating the coefficients of the terms of a binomial expansion. However, if the exponent is a negative integer, how can one use this method, seeing as factorials for negative integers are undefined. For example, how could one determine the...
  11. S

    A question regarding the definition of e

    Homework Statement In writing the definition of ##e## i.e. ##e=\displaystyle\lim_{n\rightarrow\infty}(1+\frac{1}{n})^n##, why do we denote the variable by 'n' despite the fact that the formula holds for n∈(-∞,∞)? Is there any specific reason behind this notation i.e. does the variable have...
  12. O

    MHB Why does raising a number to the power of 0 always result in 1?

    Why is base to power 0 always 1, even if it's .2^0 it =1? Is it just counting the 1 time the .2 is existing? Is that why?And - base ^ 0 is negative whatever the number is so why is that not a negative one? Because (-2)^2 is 4 but no because a negative times a negative is a positive. And...
  13. kelvin490

    Strain hardening exponent Question

    For some metals and alloys the region of the true stress–strain curve from the onset of plastic deformation to the point at which necking begins may be approximated by σ=Kεn where n is strain hardening exponent. I wonder whether this equation can be applied to engineering stress-strain curve or...
  14. B

    Modern Algebra: Proof of an exponent law

    The problem is to verify ##(g^n)^{-1} = g^{-n}## is true ##\forall n \in \mathbb{Z}##. Here is my proof: ## (g^n)^{-1} = (\underbrace{g \star g~ \star ~...~ \star g}_{n~ \mbox{copies}})^{-1} \iff## ##(g^n)^{-1} = [(g \star ~...~ \star g) \star g]^{-1}## Using ##(a \star b)^{-1} = b^{-1}...
  15. O

    MHB How do you solve for an exponent that is pi and a cube root?

    How do you solve when an exponent is pi? And a cube root. Thanks, sorry I'm slow.
  16. M

    What is the meaning and properties of negative exponents?

    hello! I want to know what happens, what means, what the properties are etc of a negative exponent I read on wikipedia "When n is a negative integer and b is non-zero, b^n is naturally defined as 1/b^−n" So based on the above, 3^-2 = 1/3^2 1) Is this correct? 2) Why does this...
  17. T

    Integrating exponent to get delta function

    Something i ran into while doing hw Homework Statement starting with \int{dx} e^{-ikx}\delta(x) = 1 we conclude by Fourier theory that \int{dk} e^{+ikx} = \delta(x) Now, i try to compute \int{dk} e^{-ikx} (I've dropped the normalization factors of 2\pi. I believe no harm is done by...
  18. bcrowell

    Exponentiation with zero base, complex exponent?

    Is there a good general definition of 0^z, where z may be complex? The cases where z is real (and positive, negative, or zero) are straightforward, but what if z isn't real? Are there arbitrary branch cuts involved, or is there some universal definition?
  19. ecoo

    Why Does Raising a Negative Number to a Power Yield a Negative Result?

    How come when you do something like -3^2=-9. Does it mean that the dash is a subtraction symbol and not a negative symbol?
  20. Saitama

    MHB Cube root of unity with a huge exponent

    Problem: Let $y=x/(1+x)$, where $$\Large x=\omega^{2009^{2009^{\cdots \text{upto 2009 times}}}}$$ and $\omega$ is a complex root of 1. Then $y$ is A)$\omega$ B)$-\omega$ C)$\omega^2$ D)$-\omega^2$ Attempt: I somehow need to show that the huge exponent is of the form $3k$, $3k+1$ or $3k-1$...
  21. T

    Solving exponential equations with x as the exponent

    My confusion comes from basic exponent rules and whether or not both sides of an equation have to have the same level of exponent, when you reduce the base for solving. If one side can have an exponent of 3, does the other side also have to be reduced to something that would also have an...
  22. N

    Matrix Inversion and the Associative Property

    Homework Statement Is it true that: (ABA^-1)^8 = AB^8A^-1 for all n x n matrix and not just for invertible matrix? My attempt: (ABA^-1)^8 =A^8B^8A^-8
  23. P

    Hyperbolic Sine - Exponent transition

    Hey I didn't understand the transition below, I'd be glad for some help thanks
  24. L

    Closed form for geometricish series (index squared in the exponent)?

    Closed form for "geometricish" series (index squared in the exponent)? Hi all, Is there a nice closed form for the following series? \sum_{k=0}^n x^{k^2} Even a decently tight upper bound and lower bound would be nice (obviously it is bounded by the corresponding geometric series \sum...
  25. anemone

    MHB Solving an Exponent Equation: How to Prove the Two Solutions?

    Hi MHB, Problem: Solve in the set of real numbers the equation $5^x+5^{x^2}=4^x+6^{x^2}$. Attempt: At first glance, we can tell $x=0, 1$ would be the two answers to the problem but how do we prove these two are the only answers? I think this problem must have something to do with the Mean...
  26. N

    How can exponent rules be solved without deleting the question?

    problem is solved.
  27. S

    MHB Manipulating Exponents to Simplify Fractional Expressions

    I'm trying to manipulate (x+1)^x+1 / ((x+1)+1)^x+1 So that I have a 1 in the numerator. If I bring the numerator down using the integer exponent rule, I'll have... 1 / ( (x+1) / (x+1) + 1 )^x+1 ? Whoops, that's not right... 1 / (x+1)^x * ((x+1)+1)^x+1 ?
  28. M

    Inequalities, trigonometric and x exponent.

    These are the two last problems I'll bother you with for a short while (I love this forum, I'll definitely stay on and hopefully be able to contribute in the future). Homework Statement Problem 1: (##-x^2##-1)sin2x > 0 , xe[0,2\pi] Problem 2: ##2^{-x^2+x+2}## < 4 Homework...
  29. anemone

    MHB Solve Exponent Challenge: Prove Equality

    Prove that $$\left( 6+845^{\frac{1}{3}}+325^{\frac{1}{3}} \right)^{\frac{1}{3}}+\left( 6+847^{\frac{1}{3}}+539^{\frac{1}{3}} \right)^{\frac{1}{3}}=\left( 4+245^{\frac{1}{3}}+175^{\frac{1}{3}} \right)^{\frac{1}{3}}+\left( 8+1859^{\frac{1}{3}}+1573^{\frac{1}{3}} \right)^{\frac{1}{3}}$$
  30. S

    What is the Polytropic Exponent, n Value for a Singular Repeating Compressor?

    Homework Statement So, after performing an experiment a number of times, to calculate the efficiency of a singular repeating compressor, I have found n ≈ 1 i.e. it equals 1.01... in all of my found values. I've now been asked to classify the type of process. Seeing as technically n > 0 and n<...
  31. C

    MHB Find derivative of function with fractional exponent?

    I need to find the derivative of R(t)=5t-3/5 are there any derivative rules I can use for this problem?
  32. F

    MHB Separation of variables, can't get y out of exponent

    Solve the DE by using separation of variables \frac{dy}{dx} = e^{3x+2y} Break up e^{3x+2y} = e^{3x}e^{2y} Move x's and y's to their own side of the equation. \frac{1}{e^{2y}} dy = e^{3x} dx Integrate both sides of the equation to get \frac{-e^{2y}}{2x}=\frac{e^{3x}}{3}+C I don't know how to...
  33. T

    Scientific notation, and an exponent question

    I'm curious but usually negative exponents mean you're going to put those numbers on the bottom (sorry forgot the exact term it is much earlier than I normally get up) (example 6^-1 =1/6 so why is scientific notation different? Or is it? (Ex: 5x10^-3=.005)
  34. W

    How to re-arrange formula with an exponent

    I have been out of school for 35 years and this is out of my reach. Can someone please re-arrange this formula solved for Tp . T = (Tp / Sa) to the .833 power I have an example in it's current form. T = 40.5 Deg C Tp = 2300mW/CM cubbed Sa = 27 CM squared
  35. J

    Derivative of Sine Function Raised to An Exponent

    Homework Statement Find the derivative of (sin x) ^ ((sin(sin x)))Homework Equations The Attempt at a Solution I get sin(sin x) * [(sin x) ^ {(sin(sinx)-1)}* cos x] The cos x isn't part of the exponent Is this right? Thanks :)
  36. M

    Proving Basic Exponent Properties for a Group

    When proving that x^m x^n = x^{m+n} and that (x^m)^n = x^{mn} for all elements x in a group, it's easy enough to show that they hold for all m \in \mathbb{Z} and for all n \in \mathbb{N} using induction on n. The case n = 0 is also very easy. But how does one prove this for n \in...
  37. M

    Lyapunov Exponent: Calculate for Linear Map xn+1= rxn

    Homework Statement Calculate the Lyapunov exponent for the linear map xn+1= rxn. Homework Equations λ = Lyapunov Exponent λ = \lim_{n \rightarrow \infty} \begin{bmatrix}\dfrac{1}{n} \sum_{i = 0}^{n - 1} ln|f'(x_i)| \end{bmatrix} The Attempt at a Solution f'(x) = r. λ =...
  38. E

    Log Function and Exponent Precedence

    Homework Statement This isn't really a specific problem, just a question if hand-writing log functions (or trig functions) is interpreted differently than when typing them into a calculator or something like Wolfram Alpha. Suppose you have this on paper: ln ex Is this the same as...
  39. A

    MHB Simplification of an equation based on exponent rules

    I have the following equation that I'm trying to simplify: $$\frac{5 + \sqrt{5}}{2\sqrt{5}}*(\frac{1 + \sqrt{5}}{2})^{x} $$ From looking at it, it seems like it could be simplified so that the right-hand side of the multiplication would be: $$(\frac{1 + \sqrt{5}}{2})^{x+1} $$ I started to...
  40. A

    Solving Exponent Problem: Find Value of x

    Homework Statement x^X^x^x^x=2. find value of x. Homework Equations taking log both sides, but it makes a equation which i am not able to solve. The Attempt at a Solution x^(x)^4=2 x^4logx=log2. what next?
  41. A

    MHB Find the finite sum of the square and cube exponent of integers

    Hey, it is clear for me that \sum_{i=1}^{n} i = \frac{n(n+1)}{2} how to find a formula for \sum_{i=1}^{n} i^2 \sum_{i=1}^{n} i^3 Thanks
  42. Square1

    Whole exponent vs. fraction exponent

    a^x means a*a*a*a... x times This makes sense for whole numbers to me, but I am sort of lost about transfering the definition one x becomes a fraction. I know that the denominator in a fraction in an exponent means "the denominator root"..., and I know what a root its. But it is a jump in...
  43. T

    Isolating a variable in an exponent

    Homework Statement So I had to find out N=Noe-ux Where No=1.5,e is the elementary charge, u=-0.068 and x=0.07 I came to the answer 1.221 Now I need to find x if u =-0.036, N=1.221 and No remains 1.5Homework Equations The Attempt at a Solution I reduce the equation to the following...
  44. T

    Question about should I do exponent rule before quotient rule for derivative

    Homework Statement ([2x+1/4x+3]^2) Homework Equations Exponent and quotient rule The Attempt at a Solution Would this become: 2* (2x+1/4x+3) then do the quotient rule?
  45. P

    MHB Exponent of convergence of a sequence of complex numbers

    Def. Let $\{z_j\}$ be a sequence of non-zero complex numbers. We call the exponent of convergence of the sequence the positive number $b$, if it exists, $$b=inf\{\rho >0 :\sum_{j=1}^{+\infty}\frac{1}{|z_j|^{\rho}}<\infty \}$$ Now consider the function $$f(z)=e^{e^z}-1$$ Find the zeros $\{z_j\}$...
  46. D

    MHB Sum of an Infinite Series with Real Exponent p

    $\sum\limits_{n = 2}^{\infty}n^p\left(\frac{1}{\sqrt{n - 1}} - \frac{1}{\sqrt{n}}\right)$ where p is any fixed real number. If this was just the telescoping series or the p-series, this wouldn't be a problem.
  47. D

    Matrix Exponent Problem: Find smallest n such that Sn = I

    Homework Statement Consider the matrix cos(3*pi/17) -sin(3*pi/17) S = sin(3*pi/17) cos(3*pi/17) Does there exist a positive integer n such that Sn = I where I is the 2x2 identity? If so, what is the smallest such integer? Explain. Excuse the poor matrix...
  48. M

    Prove: Rational Number Squared Has Prime Factors w/ Even Exponent

    I have a theory that i need to prove but I am not quite sure how to mathematically prove that it is true. Theory: When you square a rational number, each of the prime factors has an even exponent. For example, 10 --> If i square 10, which is a rational number, =10^2 =(5^2 x 2^2)...
  49. mesa

    How to use the general for of the derivative formula with a fractional exponent

    Homework Statement f(x)=x^7/2, Find the derivative Homework Equations f'(a)=limit as x approaches a; ((x+h)-x)/h The Attempt at a Solution limit as h approached 0; ((x+h)^7/2-x^7/2)/h Multiplied by the conjugate with -5/2 as exponent and came up with 2x^5/2, which is incorrect
  50. G

    MHB How to Use Exponents and Roots on a Scientific Calculator?

    On a scientific calculator, how do you get a root of a number for an exponiental? Ex.-.653846^1/12= I was taking 1/12 and making it so I can make it exponent for .653846. Obviously wrong. What am I doing here??
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