Roots Definition and 962 Threads

  1. T

    Derivative of square roots and composition functions

    how do i take the derivative of sqr(4 + sqr(3x))? My teacher wants me to do it as a chain rule composition function so i separated it into F(x)= (4+x)^1/2 and G(x)= (3x)^1/2 but i don't know where to go from here because i don't know how to take the derivative of f(x)
  2. P

    Solving Cubic Equations: Finding the Roots

    Find the roots of the equation x^3 - 3x^2 - 10x +24 = 0 I personally, have never done cubic equations so can you please explain what should i do here. Should i try with GCF, even though i don't see one yet, or is there a method to do this?
  3. I

    Derivative from Definition (square roots)

    Homework Statement Find the derivative from definition of the functin f(x)= x + squareroot(x) Homework Equations The Attempt at a Solution I only got as far as where I canceled out my positive and negative x terms in the numerator, and am left with three terms (2 of which are...
  4. B

    C10 Group, 10th roots unity with complex number multiplication

    This is for 10th root unity with complex number multiplication. I am working on closure. I have multiplied 2 elements of my set and I have so far that cos[(n+k)360/10] + isin[(n+k)360/10]. Thus I know that if n+k<=9 then there is an element in the set. Now I need to show for if n+k>9 and if...
  5. S

    LIMITS, complicated square roots and factoring

    The question is as follows: \frac{lim}{h\rightarrow0} \frac{\sqrt{1+h}-1}{h} I don't know if the way I approached the question is right, I'll give you a step by step of what I attempted: First I converted the square root into 11/2 and h1/2 (can I do that? Is that correct?) Then I...
  6. T

    Is Corruption an Inherent Part of Human Nature?

    It seems that a significant other is a large potential for corruption. i.e helping you do or get things that someone else will not do due to being illegal. This is most clear when they have a job but break the rules of conduct to help you achieve something. Being friends with someone has a...
  7. C

    Steepest descent, non-analytic roots

    Hi, For a physics class, I am supposed to evaluate the following integral I_n(a) = \int_{-\infty}^\infty \mathrm dx \, e^{-n x^2/2 + n a x} \cosh^n(x) as a function of the real non-zero parameter a, in the limit as n \to \infty using the method of steepest descent. The question adds...
  8. T

    Adding sin plus cos with fractions containing square roots

    How do I solve: [sin (pi/3)] + [cos (pi/6)]? <--- "pi" is 3.14... I think that [sin (pi/3)]= (square root 3) divided by 2 AND that [cos (pi/6)]= (square root 3) divided by 2. Now I can't remember how to add fractions containing square roots. My textbook...
  9. Astronuc

    SCIAM - High-Aptitude Minds: The Neurological Roots of Genius

    I came across an interesting article that discusses some recent research about the brain, its structure, and the relationship with aptitude. September, 2008 in SCIAM Mind & Brain Subheader - Researchers are finding clues to the basis of brilliance in the brain...
  10. P

    Range of k for Non-Real Roots: Solve x2 + (k - 2) x + (k + 3)

    Homework Statement Find the range of values of k for which the roots of the equation are not real. Homework Equations y = x2 + (k - 2) x + (k + 3) The Attempt at a Solution I have no idea...
  11. A

    How do I solve for complex roots of a polynomial function?

    Homework Statement f(x)=24x7-13x6-19x5+7x4-7x3+5x2+72x-54 Find all the roots.. Homework Equations +-(p/q)...for rational roots The Attempt at a Solution i tried factor theorem,, and synthetic division for the possible roots..i've used uppe/lower bounds but i can't get a single...
  12. K

    Efficiently Solve Roots Problems Without a Calculator

    Homework Statement Without using a calculator, find the solution to \sqrt[3]{0.64 * 10^8} The Attempt at a Solution Well, I figure I want to get everything into powers of 3. 4^3 = 64, but that leaves 100 as the denominator to get 0.64, which does not play well with ^3. I can split 10^8...
  13. X

    Showing an equation has no rational roots

    I've been working through "A Course of Pure Mathematics" and there is one problem I'm really stuck on. I'm wondering if anyone could help me out. To avoid typing it all out, I here's a link...
  14. camilus

    Roots of a polynomial (simple)

    x^3-7x^2-10x-8 = 0 what are the roots?? Sorry, I am horrible at doing these kinds of things, this is for another problem in my differential equations thread. Its been so long since I did simple roots of a polynomial, I forgot how to do it LOL! and please, this homework is due tomorrow...
  15. C

    Sum of roots, product of roots

    Hi, roots problem again x(. The roots of the equation x2 +px + 1 = 0 are a and b. If one of the roots of the equation x2 + qx + 1 = 0 is a3, prove that the other root is b3. [Done] Without solving any equation, show that q = p(p2 - 3). Obtain the quadratic equation with roots a9 and b9...
  16. C

    Real Roots of the Quadratic Equation for all Alpha Values

    Show that the equation x2 + (3\alpha - 2)x + \alpha(\alpha - 1) = 0 has real roots for all values of α \in IR. How do i do this? Do i just use the b2 + 4ac \geq 0 ?
  17. O

    Why are there 3 roots to a cubic equation?

    I find complex numbers very fascinating. But i don't understand something. Why does a cubic equation have 3 answers instead of 6? I know that there are 3 cube roots of a complex number, and the imaginary part of the complex number can be either positive or negative, so there should be 6...
  18. S

    Find all roots of x^3 + 3x^2 - 10x + 6

    find all roots of x^3 + 3x^2 - 10x + 6 the solution: identify the easy root of x=1, find the remaining roots from (x-1)(x^2+4x) using quadratic formula. The only thing i don't understand here is how to factorize to (x-1)(x^2+4x)... namely the (x^2+4x) part.
  19. M

    How can we solve complex equations with roots in the first quadrant?

    Homework Statement Determine how many roots the equation (z + \frac{i\sqrt{3}}{2})^{29} = \frac{1+i}{\sqrt{2}} has that are in the first quadrant. The Attempt at a Solution I would like to treat the right hand side in the following way. (z + \frac{i\sqrt{3}}{2})^{29} =...
  20. M

    Show a polynomial of degree n has at most n distint roots

    If F is a field, how do we prove that a non-zero polynomial with coefficients in F and of degree n has at most n distinct roots in F?
  21. E

    Real Roots of Polynomial Equations: Proving Equality of Real Roots

    [SOLVED] roots of a polynomial Homework Statement Let P(x) be a polynomial of odd degree with real coefficients. Show that the equation P(P(x))=0 has at least as many real roots as the equation P(x) = 0, counted without multiplicities.Homework Equations By the FTC, P(x) and P(P(x)) factor into...
  22. R

    Primitive roots - annoying problem

    Let r be a primitive root of a prime number p \geq 3. Prove that if p \equiv 1 (mod 4), then -r is also a primitive root of p. I've been told it's quite easy, but I can't see why it's true for the life of me :frown:
  23. D

    How do i find the roots of this?

    y = X^3 - 4x^2 -7x + 10 i have to draw a graph of this, stationary points don't matter but all else does. i know what it would look like because it is a cubic it will have 3 roots. but i don't know how to find them, i forgot :P can someone help please :)
  24. A

    2nd Order Diff Eqn. (complex roots)

    Homework Statement Prove that if y1 and y2 have maxima or minima at the same point in I, then they cannot be a fundamental set of solutions on that interval. Homework Equations Do I take the wronskian (determinant of y1, y1', y2, y2')? What would that tell me? The Attempt at a Solution
  25. D

    Number of Roots for 2x^4 - 20x^2 + 50 Curve

    how do i find the number of roots for a curve that has dy/dx 2x^4 -20x^2 + 50. if i substitute y=x^2 and use the discriminant formula i get b^2 - 4ac = 400 - 4 x 2 x 50 = 400 - 400 = 0 This way says there 1 root, answers say it has 2. Which method am i meant to...
  26. A

    Need ALGEBRA 2 HELP with square roots

    Homework Statement simplify m^(9*√5)/m^(√5) The Attempt at a Solution would that equal m^9 or m^(8*√5)
  27. A

    Inegration with square roots - calc 1

    1. Homework Statement [/b] ∫x/√(x-1)dx 2. Homework Equations [/b] I'm just stumped. I have tried u substituion with u=√(x-1) x=u^2+1 ((u^2+1)/u)du =(u+1/u)du but it doesn't seem to work and I can't integrate 1/u. I just don't know where to go with this any help would be...
  28. H

    How to find the number of roots of the function?

    [SIZE="3"][SIZE="4"]hi there h r u >? i am a high school physics teacher, and i write many software in vb.net for simulation and ... the qustion i use Newton raphson method to find a root of function but i want to determine the following 1-is the function has a root or not, and then...
  29. S

    Pol degree 3, at most 3 real roots?

    Pol degree 3, at most 3 real roots?? Well, i am trying to prove the following, indeed i think i have proved it, but it is just that it looks a little bit long, and i was wondering whether if first of all i have done it right, and second if there is any other method proving this using calculus...
  30. Z

    Find formula for sum of square roots

    Homework Statement Find the asymptotic formula for \sqrt{1}+\sqrt{2}+\sqrt{3}+\sqrt{3}+...+\sqrt{n} in the form of c \ast n^{\alpha} Identify c and alpha. (Do NOT use the fundamental theorem of calculus) Homework Equations Area under curve y = \sqrt{x} in [0, 1] is...
  31. B

    Solve Extraneous Roots: Why Do They Arise?

    Sorry for the length of the post, the problem I've included is not difficult but I wanted to have an example to help illustrate my question. solve: \sqrt{x}-\sqrt[4]{x} -2=0 . . . (x-16)(x-1)=0 The roots are 16 and 1, however when one puts them back into the original equation, 1 is...
  32. B

    Stationary points (roots) of partially derivated function

    Homework Statement f(x,y)= ln(x+y) -x^2 - y^2 1. Find the partially derivatives 2. Find the stationary points (roots) of the function Homework Equations The Attempt at a Solution Quite simple, except i don't know what to do with the ln part, this is my attempt tho f'x=...
  33. W

    What Are Fractional Roots and Why Do They Confuse?

    Starting with simple fractions, it's known that: {{{a \over b}} \over {{c \over d}}} = {{ad} \over {bc}} So when b == d: {{{a \over b}} \over {{c \over b}}} = {a \over c} But what if in the case of: {{{{1 + \sqrt 2 } \over {\sqrt 2 }}} \over {{{1 - \sqrt 2 } \over {\sqrt 2 }}}}...
  34. K

    Prove that a cubic has no rational roots

    1) Prove that the acute angle whose cosine is 1/10 cannot be trisected with straightedge and compass. ... I worked it out and at the end found out that , if I can prove that the cubic polynomial 40x3 - 30x -1 has no rational roots, then I am done. Now, is there any way to prove (e.g...
  35. R

    How can you de-rationalise the denominator of 3sqrt2/2?

    How do you get 3/sqrt2 from 3sqrt2/2?
  36. P

    Can You Find the Roots of a Complex Equation?

    Homework Statement y^6+1=0 Find the roots of this equation. (They are complex numbers) Homework Equations none. The Attempt at a Solution y^6+1=0 (zi)^6+1=0 z^6-1=0 [tex]y_1=z_1i=1i=i[/itex] How will I find other 5 roots?
  37. S

    Artin's Conjecture on Primitive Roots: Perfect Squares

    If a is a perfect square then a is not a primitive root modulo p (p is an odd prime). (from Artin's conjecture on primitive roots) http://en.wikipedia.org/wiki/Artin%27s_conjecture_on_primitive_roots This is what I know: suppose a = b^2 a is a primitive root mod p when , a^(p-1) congruent to 1...
  38. M

    Solving Quadratic Equations w/ Unequal, Real, Rational Roots

    Homework Statement Barry has just solved a quadratic equation. He sees that the roots are rational, real, and unequal. This means the discriminant is a) zero, b) negative, c) a perfect square, d) a non perfect square Homework Equations The Attempt at a Solution I think the...
  39. Y

    Solving for X involving Square Roots

    Hi, I am getting frustrated with trying to solve this equation: sqrt(x+9) - sqrt(x-6) = 3. I know that the answer is x=7 because of guess and check. I don't know how to show it algebraically. Squaring both sides will cancel out the x. Is there a trick or something this? Please help...
  40. U

    MATLAB Matlab:Chapra , ROOTS [ Bracketing Method] Help needed.

    Hello guys can anyone help me solve this in MATLAB please ? http://aycu34.webshots.com/image/43953/2003131790943491216_rs.jpg
  41. S

    Determining Equations with Squared Roots: Learn from O, P, and Q | Expert Help"

    if o,p,q are roots of the equation ax^3+bx^2+cx+d=0, determine the equation whose roots are o^2,p^2 and q^2 who can help me solve it? thank you
  42. J

    Integration by parts and roots

    Ok. I have a definite integral of e^sqroot(x) dx from x=0 to x=1. I would use u=sqroot(x) and du=1/2*sqroot(x), but I'm confused what I would set v=?
  43. V

    Are Zero's and Roots the Same Thing?

    zero's and roots... Zero's are the same thing as roots, correct? I have a question where a) askes what's the zero's. Then b) asks what are the roots. pretty sure it's the same.
  44. S

    Solving Number Theory Problems: Totient & Primitive Roots

    Homework Statement Hi guys, i have never taken number theory yet now I am forced to quickly understand it as it was required for a class i signed up. I need help with these problems and would greatly appreciate any hints or help in the right direction. Thanks. 1)Find with proof, all n such...
  45. J

    Understanding Weights & Roots: Why Does T Act Trivially?

    I'm having trouble understanding the idea of a weight space. Suppose \mathfrak{g} is the Lie alebra of G with maximal torus T and Cartan subalgebra \mathfrak{t}. The weights are the (1-dimensional) irreducible represenations of T. If we restrict any representation \rho : G \to GL(V) to T...
  46. R

    How Do You Calculate and Verify the Roots of a Complex Cubic Equation?

    Homework Statement Find the roots of the equation z^3=-(4\sqrt{3})+4i giving your answers in the form re^{i\theta}, where r>0 and 0\leq \theta<2\pi Denoting these roots by z_1,z_2,z_3, show that, for every positive integer k. z_1^{3k}+z_2^{3k}+z_3^{3k}=3(2^{3k}e^{\frac{5}{6}k\pi i})...
  47. C

    Analysis: Sequence convergence with Square Roots

    Homework Statement Given Lim Cn=c, Prove that Lim\sqrt{Cn}=\sqrt{c} Homework Equations We are working from the formal definition: for all \epsilon, there exists an index N such that For all n>=N, |Cn-c|<\epsilon The Attempt at a Solution We as a group have attempted this several...
  48. R

    Discover the Roots of Polynomials: Solving Equations and Finding Values of S_n

    Homework Statement The roots of the equation x^3-x-1=0 are \alpha,\beta,\gamma S_n=\alpha^n +\beta^n +\gamma^n (i)Use the relation y=x^2 to show that \alpha^2,\beta^2,\gamma^2 are roots of the equation y^3-2y^2+y-1=0 (ii)Hence, or otherwise find the value of S_4 (iii)Find...
  49. S

    Proofs of Descartes Rule & Polynomial Roots in College Algebra Texts

    A few of the (assumed to be good) textbooks on College Algebra discuss the use of Descartes Rule of Signs, and a test for upper and lower bounds for real zeros for polynomial functions; but these ideas are never proved in the books that I found. In which college course, and in which Mathematics...
  50. Q

    Solving a Square Root Equation with Fractional Coefficients

    Homework Statement \frac{5}{\sqrt{7+3\sqrt{x}}} = \sqrt{7 -3\sqrt{x}} Homework Equations none The Attempt at a Solution does this equal 5 = 7 - 3\sqrt{x}
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