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What is the completely factored form of x4y – 4x2y – 5y

User Isawk
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2 Answers

5 votes
y(x^2 - 5)(x^2 + 1)
I hope this helps!
User Glerup
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5.5k points
1 vote

Answer: The completely factored form is :


y(x-√(5))(x+√(5))(x-i)(x+i)

Explanation:

Since we have given that


x^4y-4x^2y-5y

We just need to simplify the above expression:

1) Take the common factor 'y' from the expression:


x^4y-4x^2y-5y\\\\=y(x^4-4x^2-5)

2) Split the middle term :


y(x^4-4x^2-5)\\\\=y(x^4-5x^2+1x^2-5)\\\\=y(x^2(x^2-5)+1(x^2-5))\\\\=y(x^2-5)(x^2+1)\\\\

3) Completely factored form:


y(x^2-5)(x^2+1)\\\\y(x-√(5))(x+√(5))(x-i)(x+i){\text{\{using }a^2-b^2=(a-b)(a+b)\}

Hence, the completely factored form is :


y(x-√(5))(x+√(5))(x-i)(x+i)

User Kostas
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