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Simplify and state restrictions. Show the factors before you simplify. a 2a2-a-1 a2–1 Х 4a? +40 2a2+7a+3

Simplify and state restrictions. Show the factors before you simplify. a 2a2-a-1 a-example-1
User Sshevlyagin
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1 Answer

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Given:


(2a^2-a-1)/(a^2-1)*(4a^2+4a)/(2a^2+7a+3)

Factorize the given expression.


\text{ Use -a=-2a+a.}


(2a^2-2a+a-1)/(a^2-1)*(4a^2+4a)/(2a^2+7a+3)

Take out the common terms.


(2a(a-1)+(a-1))/(a^2-1)*(4a^2+4a)/(2a^2+7a+3)


((a-1)(2a+1))/(a^2-1)*(4a^2+4a)/(2a^2+7a+3)
Use\text{ }a^2-1=(a-1)(a+1).


((a-1)(2a+1))/((a-1)(a+1))*(4a^2+4a)/(2a^2+7a+3)
\text{Take out the co}mmon\text{ term }4a^2+4a=4a\mleft(a+1\mright).


((a-1)(2a+1))/((a-1)(a+1))*(4a(a+1))/(2a^2+7a+3)
\text{Use 7a=6a+a in }2a^2+7a+3.


((a-1)(2a+1))/((a-1)(a+1))*(4a(a+1))/(2a^2+6a+a+3)

Take out common term.


((a-1)(2a+1))/((a-1)(a+1))*\frac{4a(a+1)}{2a(a^{}+3)+(a+3)}


((a-1)(2a+1))/((a-1)(a+1))*\frac{4a(a+1)}{(a^{}+3)(2a+1)}

The restrictions are


a\\e1,-1,-3\text{ and }(-1)/(2)\text{.}

Simplify the given expression


((a-1)(2a+1))/((a-1)(a+1))*\frac{4a(a+1)}{(a^{}+3)(2a+1)}

Cancel out the common factors.


\frac{4a}{(a^{}+3)}

The answer is :


(2a^2-2a+a-1)/(a^2-1)*(4a^2+4a)/(2a^2+7a+3),\text{ }a\\e1,-1,-3\text{ and }(-1)/(2)\text{.}
\frac{4a}{a^{}+3},\text{ }a\\e-3.

User Shantanusinghal
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