Question

How do you use the special product of a sum and difference to multiply `(3x^2+2)(3x^2-2)`?

Answer 1

Remeber

`(a+b)(a-b)=a^2-b^2`

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By setting `{(a=3x^2),(b=2):}`, we have

`(3x^2+2)(3x^2-2)=(3x^2)^2-(2)^2=9x^4-4`

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I hope that this was helpful.