Quadratic Definition and 990 Threads

I am in AP Calculus but I think I just understood what a quadratic graph is and I wanted to make sure w/ you guys that I came up w/ the right explanation. I believe a quadratic is a semicircle(only y=x^2, others are semi elipse). The only diff. is that it never gets to complete its semicircle...

Now I am trying to graph this thing. Lets say I have x^2+x+10=0 So yah... I plot them for -10<x<10 and get the y values... What I would like to know is how do I change the scale as to get zoom in and zoom out effect?

the book asks to fnd the four roots of z to the fourth power + 4 = 0 and then use to demonstrate that z to the fourth power + 4 can be factored into two quadratics with real coefficinets. I am clueless on where to start. Please help.

hey can som1 please help, i know how to find the quadratic approximation for a given function but i don't know how the quadratic approximation determines a local max/min :confused: This is with regard to multivariable functions. thanks

Today, I tried to translate the very basic "solve quadratic equations" program I made a while back in Python to C++. #Solving quadratic equations import math print print "Please enter information in accordance with ax^2 + bx + c = 0" a = input("What is...

I'm having trouble just figuring out how to set these problems up. Here is one of them. A jogger and a walker both cover a distance of 5 miles. The runner is traveling 1.5 times faster than the walker and finishes in 25 minutes less time. How fast is each going? I know it probably...

Hey guys, I've tried to do this quadratic question using the formula but can't seem to get it and don't know if its right or not. x= -b+-√b^2 – 4ac / 2a a= 37.5 b= L c= L^2 Need to find X the sub X into find L in metres. Thanks in Advance

How do you solve quadratic equations which have atleast one positive root?? The question was this: Find the value of 'm' for which the roots are such that at least one is positive. x2 -(m-3)x + m = 0 mR. Can someone help me get started? Here is my work: I checked the discriminant. for...

Hello all, I've been having some problems regarding the fall of an object in the vertical direction that has air drag which varies quadratically with speed. The problem is as shown: A gun is fired straight up. Assuming that the air drag on the bullet varies quadratically with speed. Show...

Solve the Inequality: x² - x < 0 Express the solution set as intervals or union of intervals. Use the result √a² = |a| as appropriate. What is the procedure/explanation for the answer to this question? The answer is (0,1). THat is: (0,1) is the solution set. Please help.

y^2 = 4(x+4)^3 0<=x<=2 ...y>0 Ok..so do I just simplify it to y=etc... and then find the derivative and solve..I tried this and I get a kinda long derivative..just seems like it should be easier? Thanks

Umm... I guess I don't remember this from algebra, but I have a rather basic question. Let's say you have the expression, f(x) = 4x^2 + 5x + 1 And we want to find the roots. So, \frac{-5 \pm \sqrt{5-4(4)}}{2(4)}= \{ \frac{1}{2},-1 \} Now, if we plug these into f(x) we have...

Well I'm getting pretty frustrated by this problem which arose in my research, so I'm hoping someone here might set me on the right track. I start with n random variables x_i, i=1..n each independently normally distributed with mean of 0 and variance 1. I now have two different functions...

I said that A\ell=A_{\textrm{new}}\ell\left(1+\frac{x}{100}\right)\implies A_{\textrm{new}}=\frac{A}{1+\frac{x}{100}}. Also, we know that R\propto\frac{\ell}{A}.. Therefore, R_{\textrm{old}}\propto\frac{\ell}{A} R_{\textrm{new}}\propto\frac{\ell\left(1+\frac{x}{100}\right)^{2}}{A}...

I'm learning equilibirum in class, but I am stuck on this question. DOes anyone how how to do this problem? I use the quadratic formula but end end with answers A and B, but the correct answer is A. Can someone show me step by step how to do this problem? thanks 9. At a certain temperature...

Please Help! I designed this "PROGRAM"! TO calculate the real roots of a quadratic equation... but the compiler miracle C kept saying there's something wrong around the "if" word... saying "unrecognised types in comparison" it seem SO FINE to me... what is wrong?!:eek: #include...

If I know 2 points in the +x,+y quadrant, and I want to find the f(x) = a -------- (b*x)^2 curve that passes through both points (a and b are constants). This is probably either really simple or impossible. :rolleyes:

Hey. Today i had a test on quadratics and discriminants. I think i did fairly well, but i am a bit confused about one of the questions i had in it. We were given the following quadratic equation: 12x^2 + 8mx + (4m-3) = 0 What we had to do was prove that for any integer value of m, the...

Hey. I've got a question to solve, and I am a bit confused. Ok. I understand what the question is asking, i just don't know how to do it. I am oretty sure that if \delta < 0, thenthere are no real solutions, but I am not sure about 1 or 2 solutions. I played around with quadratic functions...

I have this problem I've been looking at for about 6 hours. It requires me to find all primes p such that 3 is a quadratic residue (mod p). All I could come up with is that every prime p ending in a 1 makes 3 a QR mod p. But this came after using excel and computing all primes. Surely there...

I'm supposed to use this equation: y = x^2-8x+7 To solve the following questions: 1) What is the value of the discriminant? 2) Find the roots by factoring and solving. 3) Find the roots by using the quadratic equation. Can anyone give me some help? Thanks! :)

A large dealership had been selling new cars at $6000 over the factory price. Sales have been averaging 80 cars per mouth. Because of inflation, the $6000 markup is going to be increased. The marketing manager has determined that, for every $100 increase, there will be one less car sold each...

Ok, I’m having trouble solving this equation: -x^4+200=102x^2 The solutions I got for it are x=10 and x=-10 which both work as solutions but the last one I got, x= the square root of 2, doesn’t work. My textbook offers the only advice for doing this type of...

i keep getting nonzero off diagonal elements when i try to reduce to simple sum of squares, of the equation 2 x_{1}^{2}+2x_{2}^{2}+x_{3}^{2}+2x_{1}x_{3}+2x_{2}x_{3} what i have is \left(\begin{array}{ccc} x_{1} & x_{2} & x_{3} \end{array}\right) \left(\begin{array}{ccc} 2 & 1 & 0 \cr 1 &...

Ok, the question I have is attached. What I have done is found the general solution: (Question was seperable, so it was easy) y = x^2 - 2x + c But I don't kwow what/how to do is finding the initial conditions where there are: (a) No solutions (b) more than one solution (c) precisely...

"Let Q(v)=<v,v> be the quadratic form associated to a real or hermitian inner product space. ... " What's a quadratic form?

" the height "h" meters of a cricket ball after being struck by a batsman is given by the equation h=1+x-(x^2/40) where x meters is the horisontal distance traveled by the ball from the bat. how far would the ball travel before it hits the ground?" I have: using pythagoras...

Hi, I just need to learn in drawing graphs using a quadratic equation. Also I need to know how to find the minimum and maximum point and the line of cemetry from the equation (I need to know by proving it in the equation) Has anyone got any website to clearly learn about this? I know...

hi, I need to learn very well about quadratic equations. Can anyone give me a site to learn about these equations? Thanks:smile:

Hello All I am trying to figure out how to determine if there are two, one, zero, or infinitely many roots for given formula ax^2 + bx + c. Are there any easy ways to determine this without having to use the quadratic formula? Thanks P

I desperately need some help with sketching cylinders and quadratic surfaces. We did this in first year and I understood it then but now that I look at it, I have no idea where to start. Oh and yes I have been into talk with my ta quite a few times but I still don't quite understand; I'll go...

okay i need to solve the quadratic y = -x^2 + 5x + 6 and need to find the coordinates of the vertex of the curve by factorising y = -(x^2 - 5x - 5) y = -(x + 1)(x - 6) so when y = 0, x = -1 and x = 6 (that parts simple) .............. At the vertex x = (-1 + 6) / 2 = 5/2 (as...

1. (a) If the roots of the equation 2(x)^2 + kx + 100 = 0 are positive, find the possible range of k. (b) If, in addition, one root is twice the other, find the roots and the value of k. I have tried (a), but incorrect: discriminate > 0 k^2 - (4)(2)(100) > 0 k^2...

Hi! I'm new here so if this has been covered please accept my apologies. I'm having trouble proving the equation from: ax²+bx+c=0 to the solutions x=(-b(+/-)√b²-4ac)/2a I've been told to complete the sqaure of ax²+bx+c, then rerrange to give x, but I just can't get it! If you could show the...

I've been able to prove that the set {8n+7} has infinite primes by manipulating Fermat's Theorem, but I'm trying to reprove it using quadratic residue and Legendre Polynomials. I've been able to show that for p=8n+7, (2/p)=1 and (-1,p)=-1 So it follows that (-2/p)=-1. And that (-2/p)=1 iff...

hey can you help me solve these, I've got 20 problems..and i only need is this problem so that i have an idea of answering the others An engineer can decrease by 2 hours the time it takes to travel 200km. If he increases the speed of the freight train by 5km per hour, what is the original...

Students from a history class prepare a trip that will cost them a total of $189 that will be shared between them. The day before the trip, 6 students discovered that they can't participate in the trip. To avoid cancellation, the rest of the class decided to pay an additional $2 each. How many...

I have a function y = \sqrt{ax^2 + bx +c}, and 2 sets of points {x_i},{y_i} that need to be fit on this curve. First in this problem, I need to somehow convert this nonlinear function into linear and then apply least square methods to determine a,b,c. What I came up is ofcouse squaring both...

http://www.mste.uiuc.edu/users/exner/ncsa/quad/ There's another way of writing the quadratic formula...but how do I derive the 2nd formula using the 1st one? I've tried for hours and I can't get it. I would really appreciate any help.

How would I solve this equation: 3(x-3) + 4x+7= 5x-3 And How would I solve these Quadratic Equation: x^2 + 7x + 12 = 0 3x^2 - 10x + 8 = 0 8y^2 + 18y = 5 = 0 Thanks.

Hey, could someone please help me with this problem? I just want to know why the graph of Quadratic Equation are symmetric and why does the maxima and minima ( = -b/2a ) the mean of the two roots? One more thing I didn't get was what does the a represent in ax2+bx+c ( ax square+bx+c)? I know for...

Hi, I may not be thinking straight or something, and I am having trouble with this question, please help!: Given that 'p' is real, find the set of values of 'p' for which the roots of: (2p+1)x^2 - 10x + p-2 = 0 a) Are real b) Have a sum>5 Im thinking along the lines of: alpha+beta =...

Hi. It's late in the game for me to still be banging my head over this one, so I was hoping for some priceless tips from those who are doing it in their sleep.. PLeeeasse :redface: I know I should remember the Quadratic formula better than I do, but I was encouraged not to resort to it...

I'm having some trouble figuring out how to simplify the following problem. I know that i= the sq root of -1, and that i^2=-1, but I'm not sure how to approach this problem. sq.rt.(-x^2-4x-3)

Hi, I'd like to know which property proves the following simple result. Let p be a prime greatest than 3. r is a quadratic residue of p if there exists a such that: a^2 \equiv r \pmod{p}. Since p is prime, there are \frac{p-1}{2} different residues (not counting 0). Now, if you sum them...

This was on a test but I couldn't quite solve for x: 5^2^x + 4(5)^x = -3 let 5^x = y y^2 + 4y + 3 = 0 (y + 1)(y + 3) = 0 So I end up with 5^x = -1 or 5^x = -3, but I don't think that makes sense... what am I doing wrong? It must be something dumb I'm doing :shy:

hey , i tried deriving another method for solving a quadratic equation ,and here is wat i came across +or - sqrt ([b^2-2ac+or-(b sqrt[b^2-4ac])/2a^2) i hope u get this correctly its read plus or minus square root of b^2-2ac plus or minus b root b^2-4ac all divided by 2a^2,remember the...

Hi, How is the roots of a quadratic equation related to the distance from the x-axis at where the root is - where ... ax^2+bx+c=0 and ... x = (-b +- SQRT(b^2-4ac))/2 Can someone help me to establish where this distance relationship to the x-axis and the root come from? Thx! LMA

The quadratic equation x^2 + mx + n = 0 has roots that are twice those of x^2 + px + m = 0, and none of m, n, p is zero. What is the value of n/p? I'm stuck and don't know where to begin.

Hey I have a test today and can't figure out how to solve certain quadratic equations. We are doing solving the equations by completing the square using these steps: 1. divide each side by coefficient of x squared 2. rewrite the equation with the constant on right side 3. complete the...