need help!!! urgent will award medal!!!
what is the restriction point of this
What is the restriction on the product of
@quickstudent @Whitemonsterbunny17 @worldsgreatest @Elsa216 @Cosmichaotic @study100
A fraction means a division. Have you heard of a division which is undefined?
the restriction point? so only 1. I guess you have to factor our those trinomials.
Specifically, dividing by what is undefined?
well, with just looking at the equation now? @mathstudent55
it wants the restriction on the product
@rayanashef98 Let me ask again. You can take any number and divide by anything you want, except by one single number. What is the number you can't divide by because division by that number is undefined?
these are the options: , x ≠ -3 x ≠ 3 x ≠ 1 x ≠ -2
would it be 0 @mathstudent55
Exactly.
Division by 0 is not allowed.
@mathstudent55 seriously math, you need to become a math teacher :))
then you'll be mathteacher55 :))
Remember, a fraction is a division of a numerator by a denominator. In your expression, you have 2 fractions. Each fraction has a denominator. Each denominator is an expression is x. Any value that causes either denominator to be zero must be excluded because, as you well know, division by zero is not allowed.
Now we begin by ignoring the numerators and only thinking about the denominators.
ok
Let's look at the right denominator only because it's a simpler expression and we'll deal with it faster.
alright
The right denominator is x + 2. The expression x + 2 may or may not equal zero, depending on what x is equal to. We need to find out what value of x would make the expression x + 2 equal zero. We do the opposite of what we want. We purposely set x + 2 equal to zeros and solve for x.
x=2
x + 2 = 0 Subtract 2 from both sides to get: x + 2 - 2 = 0 - 2 x = -2
right -2
We found one restriction: \(x \ne -2\) x cannot be -2.
ok
so that is the answer then
bc its multiple choice so it only can be one of them
Now we need to do the same to the left denominator. Again we do the opposite of what we want. We don't want the denominator to equal zero, so we set it equal to zero to find the values of x that cause a zero in the denominator. Then those values will be restrictions on x.
Not so fast. Let's continue.
ok
Now we set the left denominator also equal to zero and we solve for x. \(x^2 - 2x - 3 = 0\) We factor the left side: \((x - 3)(x + 1) = 0\) We set each factor equal to zero: \(x - 3 = 0\) or \(x + 1 = 0\) We solve each small equation: \(x = 3\) or \(x = -1\)
ok
so x can't equal 3 -1 or 2
Correct.
thnx
technically math is right! :) but after the product, one answer remains x cannot be equal to 3
Now we do one more step. We actually multiply the fractions together, factor the numerators, and reduce as much as possible.
\(\dfrac{x^2 + 3x + 2}{x^2 - 2x - 3} \times \dfrac{x^2 + 4x + 3}{x + 2} \) \(= \dfrac{(x + 2)(x + 1)(x + 3)(x + 1)}{(x - 3)(x + 1) (x + 2)} \) Now we simplify the fractions (we reduce it): \(= \dfrac{\cancel{(x + 2)}\cancel{(x + 1)}(x + 3)(x + 1)}{(x - 3)\cancel{(x + 1)}\cancel{(x + 2)}} \) \(= \dfrac{(x + 3)(x + 1)}{x - 3}\) From here you see that the only denominator that remains is x + 3, so only x = -3 is a restriction.
oh @mathstudent55 x=3
denominator is x-3
Thanks for the correction. It's great to see that at least you are still awake! That makes one of us awake. Thanks. Since the denominator has x - 3, we set x - 3 = 0 and we get x = 0 as the restriction.
Everything is explained so well. I actually crossed our wrong factors when I did the problem haha. :P Good work!
Sleep if you're tired! Your health is uttermost important. :)
Oh I was horrible when I'm tired too haha xD I did the problem all wrong once when I was half asleep. Hope to see you again soon mathstudent!
It's only 8:05 pm here, but my half dead state starts kicking in around 10 PM
Actually I think there is a problem with this problem. Once you simplify the expression to \(\dfrac{(x + 3)(x + 1)}{x - 3}\) then the restriction of x = 3 is still apparent because it is still visible in the denominator. Since the binomials x + 1 and x + 2 are no longer in the denominator, those restrictions must be mentioned. Therefore, \(\dfrac{x^2 + 3x + 2}{x^2 - 2x - 3} \times \dfrac{x^2 + 4x + 3}{x + 2}\) = \(\dfrac{(x + 3)(x + 1)}{x - 3}\) for \(x \ne -2\) and \(x \ne -1\)
You still have 2 hours then. I need to go. Bye.
Bye! See you again soon! :) Have a good rest ! <3
Thanks. Good night.
i need help with another!! @study100
What is the restriction on the product of
@study100 r u there?
I'm here :) Sorry I had to take care of my baby cousin
https://drive.google.com/file/d/0BxHGvu5cxsDlbVdqS2hNeFhmOHlBbjQydVBFdk91NlZUemNJ/edit?usp=sharing
thnx @study100
You're welcomed :)
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