I need help with finding the simplified form of an equation.
\[ \frac{ 1 }{ x } - \frac{ 2 }{ x^{2}+ x }\]
to combine the two, need to change to same denominators
x^2 +6 x = 2z + 6 for
I'm sorry where did the 6 and z come from?
like dan said, equal the denominators
Please look at the expression you've typed in, and determine what the lowest common denominator (LCD) is. You'll need the LCD to combine those two fractions into one.
hint: x^2+x=x*(x+1)
To find the LCD, you could multiply the two given denominators together. but Alex has a better idea: He sees that the two given denominators share a common factor, which is x. The den. of the second fract. is done (although it'd look nicer if you factor it as Alex has done). What do y ou have to do to the 1st fraction to obtain the same LCD in the denominator? Hint: You must multiply its numerator and its denom. by the same thing.
I'm not sure what I would do, all I know is that I need to get \[x^{2}\] into my first denominator.
It's more than just x^2. If done correctly, your numerator in the first fraction will become a polynomial in x.
Note that you have "x" in the denom. of the first fraction. Multiply that x by ... what? ... so that you have the LCD in BOTH fractions.
by two?
First, type in the LCD. See Alex's work (above). Second, determine by what quantiity you must multiply the x in the denom. of the 1st question to get the LCD there.
So my denominator's would be x(x + 1)?
To get that for my first denominator I need to multiply x by (x + 1), correct?
yes, very good. if you mult
the den. of the 1st fract. by x+1, you must also mult. the num. by the same quantity. Do this and type in your results, please.
Thus, \[\frac{ 1 }{ x }+\frac{ 2 }{ x^2+x }becomes. what?\]
would my x^2 + x become x(x + 1) as well?
The second fraction doesn't change, unless y ou wish to factor the denom. (which looks better). The first fraction becomes
\[\frac{ x+1 }{ x(x+1) }\]
And now the fractions have the same denominator.
Okay, so then what happens with my second numerator?
Nothing. No need to change it, because the denom of that fraction is already the LCD. Now combine those two fractions, now that they have the same denom. This requires that y ou add together the numerators. Be careful with signs.
Okay so I first changed my denominators to x(x + 1), then I change my first numerator by multiply it by (x + 1) which gives me \[\frac{ x+1 }{ x(x+1) }\] and then I just subtract my second numerator from my first correct? Since in my original equation I was subtracting?
Which leaves me with x-1 over x(x+1)
Great job!!!!
:) thank you!
Hope you'll review our discussion so that you can apply this procedure to solving similar problems in the future. You're welcome!!
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