General Question

emeraldisles's avatar

Can anyone help me with rational expressions?

Asked by emeraldisles (1949points) March 21st, 2012

I’m not asking anyone to do homeowk, but I need help on these two styles of problems. The first one asks me to simplify the complex rational expression. It reads as 7/ y^2 +4y+3/ 1/y+3 + 4/y+1. It is 7 over y squared plus, 4y plus 3 over two other fractions 1 over y+3 plus 4 over y+1. Its a fraction over two fractions. I believe I have to factor out the denominators and multiply by the LCD?The second problem asks me to add 8y/ y^2 +12y+27 + 4/y+3. The problem is 8y over y squared plus 12 y , plus 27 plus the fraction of 4 over y+3. I’m sorry that I can’t write this out in fraction form. I’m confused.

Observing members: 0 Composing members: 0

6 Answers

yankeetooter's avatar

Add some parentheses. so I’m clear on what the problem should read, and I’ll see what I can do…

emeraldisles's avatar

1. ( 7/y^2+4y+3)/ ( 1/y+3)+( 4 /y+1). It should be 7 over y squared plus 4y plus 3, over 1over y plus 3 with a plus sign then 4 over y plus 3. The second one reads ( 8y/ y^2 +12y+27)+( 4/y+3). It should reas in the fraction form of 8y over y squared plus 12 y, plus 27 + 4 over y+3.

ratboy's avatar

Still too few parentheses. Is it (7/(y^2+4y+3)) / ((1/(y+3))+(4/(y+1)))?

If so, then factor y^2+4y+3 and you’ll see what you need to do.

Similarly for the second one.

emeraldisles's avatar

Ther are no parentheses in these problems. I figured out that y^2+4y+3 needs to be factored out which would help give me the lcd.

Response moderated (Unhelpful)
ratboy's avatar

(1 / A) + (4 / B) = (B + 4 * A) / A * B;

(7 / A * B) / ((B + 4 * A) / A * B) = (7 / A * B) * (A * B / (B + 4 * A));

Cancel A * B in the denominator of the first fraction with the A * B in the numerator of the second.

Answer this question

Login

or

Join

to answer.

This question is in the General Section. Responses must be helpful and on-topic.

Your answer will be saved while you login or join.

Have a question? Ask Fluther!

What do you know more about?
or
Knowledge Networking @ Fluther