determine the restriction of
3x
2x-4
Answers
Answer:
Let's first find the restrictions:
This can be done by factoring the denominator of the expression.
3x−2x+3+7(x−4)(x+3)
A restriction in a rational expression occurs when the denominator equals 0, since division by 0 in mathematics is undefined.
Therefore, we must now set the factors in the denominator to 0 and solve for x. These will be our restrictions.
x+3=0andx−4=0
x=−3andx=4
Therefore, x≠−3,4
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Now, let's simplify:
This can be done by placing everything on a common denominator.
Since both expressions already has (x+3) as a factor in the denominator, and only one has (x−4), we must multiply the expression to the left by (x−4) to make it equivalent to the one on the right.
(3x−2)(x−4)(x+3)(x−4)+7(x+3)(x−4)
=3x2−14x+8+7(x+3)(x−4)
=3x2−14x+15(x+3)(x−4)
The trinomial in the numerator is factorable. Always factor it when possible to see if anything can be simplified. You will be docked marks if you don't simplify fully. I factored this one and nothing needs to be eliminated. This is in simplest form.
Hopefully this helps!