quadratic equations?

Question

ok im in algebra 1 and we are learning about quadratic equations...but i dont get the types of problems that have f(x)=3 or something like that. can anybody help me?

Answer 1

f(x) means a function of x

if it helps you - think of it as "y" when you are plotting a graph on the x and y axes

They are calling it f(x) so they can do other funny things like have another function they will call g(x)

Or they can do some maths to the f(x) (do the calculus thing) and get f'(x) which is the differentiated function.

f(x) = 3 doesn't actually mean to substitute 3 in wherever you see x

x = 3 means that

The line f(x) = 3 is like the line y = 3 and is a horizontal line which cuts the y axis at (0,3)

Sometimes when they give you f(x) = x^2 and then they say that f(x) = 3 then you will have to do some algebra and work out that 3 = x^2 and hence x = +/- SQRT(3)

So when you have a quadratic equation, it will look something like: f(x) = 5x^2 - 4x + 3

This describes a parabola. Go to the function grapher site and have the computer draw your parabola.

Draw a few other parabolas

f(x) = x^2

f(x) = x^2 + x - 1

f(x) = 5 - x - x^2

You can see that some of them touch the x-axis. Some of them lie above (or below) the x-axis. Some of them cut the x-axis twice.

You may eventually be asked to find the "Zeros" or "roots" of the parabola - this is where f(x) = 0

for example 0 = x^2 + x - 1
or 0 = 5 - x - x^2

You can see where they are on the graph. You'll have to learn some maths to find out what they are mathematically.

Also - parabolas have a "vertex" or turning point. This is where they stop going down and then turn and start going up (or vice versa).

Have a read of the wiki pages.

Answer 2

One straightforward time period that seems regularly is "equations." for most, it is a buzz word this is recognizable as a math time period yet really expertise the time period ought to sometime destroy out human beings. both maximum straightforward equations are linear equations and quadratic equations yet, of route, in elementary terms giving an equation a recognition does no longer inevitably clarify what it truly is. So, a clearer definition of what precisely both maximum straightforward equations - linear and quadratic equations - is necessary. A linear equation refers to a particular equation this is graphed on a promptly line. also, a linear equation possesses on the line one variable this is oftentimes called "X" and "X" will continually be of a level this is a million at maximum. (this is, there are not any exponents; yet when you're looking for exponents then be affected human being because we receives to them presently!) a straightforward get mutually of a linear equation will be 1x + 2 = 3. obviously, x would equivalent a million in this actual get mutually and it must be discovered through in elementary terms utilizing a touch algebra on the equation to decide X. 3 minus 2 equals a million. therefore, X could equivalent one as a million x a million equals one. And, nope, no longer all linear equations are that straightforward as they arrive as complicated as 6(x + 3) = 24 (x +0), besides the indisputable fact that the classic aspect of putting apart x to locate the answer would not replace. A quadratic equation is basically different from a linear equation in a unmarried understand: one or extra of the figures is squared. (The word quadratic derives from the Latin word for squared) the classic form of a quadratic equation is ax2 + bx + c = 11. In the style of equation, if a = a million, b = 2 and c = 3 then X could equivalent 2. all of us comprehend this because 2 squared is 4 and four x a million = 4. 2 x 2 = 4. As with a linear equation, there must be extra complicated variations of a quadratic equation yet in basic terms with the straightforward and complicated linear equations difficulty-free algebraic operations can yield the finished answer.

Answer 3

yes sure i can help you in algebra or any other topic in math. just ask questions.
these days by coincidence i am teaching quadratic equations there factorization,finding roots by using splitting the middle term method and using general formula and remainder and factor theorems.

Answer 4

if f(x)=3 then anywhere there is an x plug in a 3 and crank out the rest of problem! its easier than teachers lead you to believe!

Answer 5

ax^2+bx+c=0
a is not zero

Answer 6

http://mathworld.wolfram.com/QuadraticEquation.html