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I didn’t understand this question, please help thank you very much

I didn’t understand this question, please help thank you very much-example-1
User Thiago Belem
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1 Answer

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Hello there. To solve this question, we'll have to remember some properties about finding the common denominator of a sum of fractions.

Given the fractions:


(5y^2+2)/(y^2+7y+10)+(3)/(y+2)

We start by factoring the expression in the denominator of the first fraction.

Notice it is something of the form x² - Sx + P, where S = -7 and P = 10.

S and P are the sum and the product of the roots of the expression. In this case, we can easily find values that would give us a sum of -7 and a product of 10:

y = -2 and y = -5

Thus, we write it as:

y² + 7y + 10 = (y + 2)(y + 5)

Then we have:


\frac{5y^2+2}{(y+2)(y+5)_{}}+(3)/(y+2)

Now, to find the common denominator, we calculate the least common multiple of the expressions:


\mathrm{lcm}((y+2)(y+5),(y+2))=(y+2)(y+5)

We can calculate it as:

Therefore this is the common denominator of the fractions, in its factored form.

I didn’t understand this question, please help thank you very much-example-1
User Hans Bouwmeester
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