quadratic

  1. O

    Quadratic word problem

    Hi, I hope someone can help me determine the quadratic equation for the following word problem: Note that below is question 1: I was easily able to develop the equation for question 1, which the question prompt for a linear equation, as follows: Now for question 2, I need to develop...
  2. K

    Difference of Squares Problem

    I was doing a problem on practicem 4x^2 - 361. I know how to use the quadratic formula but is it impossible to factor difference by squares when the second number is a prime number. can you factor using a fraction or something?
  3. A

    Why is discriminant taken to be zero when finding the range of y?

    So, I was given a question which went like this y=Quadratic/Quadratic, find range of y. So, my teacher said that I needed to make a quadratic in x by taking all the terms in one side and then I had to make the discriminant greater than or equal to zero since x is real. But, discriminant is...
  4. A

    How to solve this quadratic problem?

    This is what I've tried so far
  5. J

    Finding speed with basically just distance.

    Hi, I'm currently in the process of trying to learn how to use quadratics to find out speed/distance/time etc. My program that I'm taking is often very unclear and skims over topics regularly. The example I was given to learn the process was fairly straightforward and easy to learn, however the...
  6. C

    equations in quadratic form

    2x^-2/3-3x^-1/3-2=0(Doh)
  7. M

    Quadratic equations

    hello, so i know how to solve quadratic equations, except when they give me a solution. What exactly do i do with the solution?
  8. W

    Local quadratic approximation

    I wanted to implement some penalized regression parameter estimation algorithm by Fan&Li (http://sites.stat.psu.edu/~rli/research/penlike.pdf, section 3.3), but cannot catch the idea of some details. More specifically, I don't quite understand how local quadratic approximation is derived...
  9. B

    Complex Roots of a Quadratic

    Hi I am trying to solve a 2nd order ODE and after multiplying through by e^(theta x) the co-efficients I am left with are: a=1, b=4, c=25 I can then solve this as far as -4 plus or minus sqrt(16-100)/2 Leaving -4+- sqrt(-84)/2 I can see this can be simplified to say -4+2i(sqrt21)/2 = -2+i...
  10. rebirth61213

    Probability problem involving a quadratic. (not sure where I went wrong w/ this).

    The question goes like this: "The probability of a biased coin showing heads on any throw is p. The probability that the coin shows heads exactly once in two throws is 0.42; find the two possible values of p." I'm not quite sure where I went wrong w/ this... Let p = prob of head x = prob of...
  11. T

    Find the quadratic approximation near x = 1 for y = f(x) given by y = x ln x

    Find the quadratic approximation near x = 1 for y = f(x) given by y = x.ln x, where x > 0.
  12. C

    Quadratic Models Help

    Hi, could you please help me with this quadratic models question? I'm confused :) A farmer has 60m of fencing with which to construct three sides of a rectangular yard connected to an existing fence. a) The width of the yard is x m and the area inside the yard is Am^2, write down the rule...
  13. M

    Please NEED help on quadratic find possible values of k

    hello I am currently studying for an exam (yr11) The question I'm stuck with states that : If 2kx^2-4kx+4k=4x-7 has distinct roots find the possible values of k I have to stick with real number solutions what ive done so far 2k(x2)+(−4k−4)x+(4k+7)=0 Applied the Quadratic Formula, with...
  14. G

    A couple of quadratic equation questions!

    So i am lost at how to set these problems up so that i can solve them using the quadratic equation, here are the two problems: 1) A flat screen computer monitor is 37.0 cm wide and 31 cm high with a uniform edge around the viewing screen. if the edge covers 20.0% of the monitor front, what is...
  15. H

    Quadratic Equations!

    reviewing for the upcoming finals and I came across this particular problem on one of my previois tests that I incorrectly answered; I was unable to ask my math teacher since I noticed this problem AFTER school. The Problem Goes: Y=-4x+10x+6 is a quadratic equation that represents the height...
  16. G

    Solving Quadratic Trgonometic equations

    Hello I am having a problem with this question -2cos2x-2sinx=0 -2(1-2sin2x)-2sinx=0 4sin2x-2sinx-2=0 then factor (4sinx+2)(sinx-1)=0 sinx=-1/2 sinx=1 I have solved for sinx=-1/2(7pi/6,11pi/6) but Im having trouble with sinx=1 x=sinx-1(1) x=90 How do I represent this? Since sinx is...
  17. F

    Find quadratic Equation with Given Zeroes AND 1 point

    Given Zeroes : x = 1 - sqrt(2) and x = 1 + sqrt(2) and given 1 point that it passes through (2,4) write an equation I got as far as 4 = a[ 2 + (1 - sqrt(2) ] [ 2 + (1 + sqrt(2) ] and now I'm completely stuck I don't even know if I did that part properly.
  18. M

    Quadratic Equation

    I am curious on this equation: (4y+5)^2 -15(4y+5)+56=0 So I know how to solve it from looking it up. But what if I wanted to Expand the problem by multiplying (4y+5)(4y+5) and the same with bx, -15(4y+5), I would then get 16y^2-20y+6=0 And through ac method answer would be y=12 and y=8...
  19. R

    Determine whether linear, quadratic or exponential...

    1. Determine whether linear, quadratic or exponential... This is what I got for 0 to 5: http://www.wolframalpha.com/input/?i=%280%2C2.7%29%281%2C4.1%29%282%2C1.5%29%283%2C-5.1%29%284%2C-15.7%29%285%2C-30.3%29+ This is what I got for 5 to 9...
  20. C

    Hard Quadratic Equation

    Hi everyone ! I am in a struggle today, with a hard quadratic equation problem : Let's suppose that, with x being an element of [-1;1], we have : |ax^2 +bx+c| <= 1 with a=/=0. ( <= means inferior or equal to) Show that |b| <= 8 and that this...